Document and Entity Information	9 Months Ended
Document and Entity Information	Sep. 30, 2013	Oct. 31, 2013
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2013
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q3
Entity Registrant Name	MACROGENICS INC
Entity Central Index Key	0001125345
Current Fiscal Year End Date	--12-13
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		25,020,288

Consolidated Balance Sheets (USD $)	Sep. 30, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 33,569,198	$ 47,743,155
Accounts receivable	2,281,282	2,046,219
Prepaid expenses	1,103,449	137,634
Total current assets	36,953,929	49,927,008
Restricted cash	404,850	404,850
Property and equipment, net	4,469,882	3,267,796
Other assets	147,246	147,246
Total assets	41,975,907	53,746,900
Current liabilities:
Accounts payable	1,798,228	3,739,125
Accrued expenses	939,811	1,237,025
Lease exit liability - current	1,229,454	628,768
Deferred revenue - current	21,298,318	24,123,176
Total current liabilities	25,265,811	29,728,094
Lease exit liability	8,378,184	9,445,171
Deferred rent liability	2,888,688	2,801,653
Preferred stock warrant liability	679,296	52,947
Deferred revenue, net of current portion	8,812,342	19,956,343
Total liabilities	46,024,321	61,984,208
Stockholders' equity (deficit):
Common stock, $0.01 par value - 425,000,000 shares authorized, 2,124,624 and 1,098,914 shares issued and outstanding at September 30, 2013 and December 31, 2012, respectively	21,246	10,989
Treasury stock, at cost; 14,381 shares at September 30, 2013 and December 31, 2012	(57,742)	(57,742)
Additional paid-in capital	165,569,134	164,334,646
Accumulated deficit	(172,528,254)	(175,472,403)
Total stockholders' equity (deficit)	(4,048,414)	(8,237,308)
Total liabilities and stockholders' equity (deficit)	41,975,907	53,746,900
Series A-1 Convertible Preferred Stock [Member]
Stockholders' equity (deficit):
Convertible preferred stock	268,748	268,748
Series A-2 Convertible Preferred Stock [Member]
Stockholders' equity (deficit):
Convertible preferred stock	73,646	73,646
Series B Convertible Preferred Stock [Member]
Stockholders' equity (deficit):
Convertible preferred stock	714,012	714,012
Series C Convertible Preferred Stock [Member]
Stockholders' equity (deficit):
Convertible preferred stock	1,109,522	1,109,522
Series D-1 Convertible Preferred Stock [Member]
Stockholders' equity (deficit):
Convertible preferred stock	144,462	144,462
Series D-2 Convertible Preferred Stock [Member]
Stockholders' equity (deficit):
Convertible preferred stock	$ 636,812	$ 636,812

Consolidated Balance Sheets (Parenthetical) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	425,000,000	425,000,000
Common stock, shares issued	2,124,624	1,098,914
Common stock, shares outstanding	2,124,624	1,098,914
Treasury stock, shares	14,381	14,381
Series A-1 Convertible Preferred Stock [Member]
Convertible preferred stock, par value	$ 0.01	$ 0.01
Convertible preferred stock, shares authorized	26,874,792	26,874,792
Convertible preferred stock, shares issued	26,874,792	26,874,792
Convertible preferred stock, shares outstanding	26,874,792	26,874,792
Aggregate liquidation preference	$ 27,000,000	$ 27,000,000
Series A-2 Convertible Preferred Stock [Member]
Convertible preferred stock, par value	$ 0.01	$ 0.01
Convertible preferred stock, shares authorized	7,364,582	7,364,582
Convertible preferred stock, shares issued	7,364,582	7,364,582
Convertible preferred stock, shares outstanding	7,364,582	7,364,582
Aggregate liquidation preference	7,000,000	7,000,000
Series B Convertible Preferred Stock [Member]
Convertible preferred stock, par value	$ 0.01	$ 0.01
Convertible preferred stock, shares authorized	71,401,237	71,401,237
Convertible preferred stock, shares issued	71,401,237	71,401,237
Convertible preferred stock, shares outstanding	71,401,237	71,401,237
Aggregate liquidation preference	31,000,000	31,000,000
Series C Convertible Preferred Stock [Member]
Convertible preferred stock, par value	$ 0.01	$ 0.01
Convertible preferred stock, shares authorized	110,952,217	110,952,217
Convertible preferred stock, shares issued	110,952,217	110,952,217
Convertible preferred stock, shares outstanding	110,952,217	110,952,217
Aggregate liquidation preference	45,000,000	45,000,000
Series D-1 Convertible Preferred Stock [Member]
Convertible preferred stock, par value	$ 0.01	$ 0.01
Convertible preferred stock, shares authorized	30,000,000	30,000,000
Convertible preferred stock, shares issued	14,446,227	14,446,227
Convertible preferred stock, shares outstanding	14,446,227	14,446,227
Aggregate liquidation preference	9,400,000	9,400,000
Series D-2 Convertible Preferred Stock [Member]
Convertible preferred stock, par value	$ 0.01	$ 0.01
Convertible preferred stock, shares authorized	75,000,000	75,000,000
Convertible preferred stock, shares issued	63,681,176	63,681,176
Convertible preferred stock, shares outstanding	63,681,176	63,681,176
Aggregate liquidation preference	$ 41,500,000	$ 41,500,000

Consolidated Statements of Operations and Comprehensive Income (Loss) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Revenues:
Revenue from collaborative research	$ 20,111,173	$ 15,532,680	$ 42,015,994	$ 50,283,510
Grant revenue	120,895	548,864	1,112,238	3,744,047
Total revenues	20,232,068	16,081,544	43,128,232	54,027,557
Costs and expenses:
Research and development	11,087,919	11,968,253	32,233,828	36,924,987
General and administrative	1,986,555	1,514,334	7,322,974	6,640,740
Total costs and expenses	13,074,474	13,482,587	39,556,802	43,565,727
Income (loss) from operations	7,157,594	2,598,957	3,571,430	10,461,830
Other income (expense)	(553,612)	1,557	(627,281)	4,752
Net comprehensive income (loss)	$ 6,603,982	$ 2,600,514	$ 2,944,149	$ 10,466,582
Basic net income (loss) per common share	$ 0.14	$ 0.00	$ 0.00	$ 0.00
Diluted net income (loss) per common share	$ 0.01	$ 0.00	$ 0.00	$ 0.00
Basic weighted average number of common shares	1,184,507	1,092,307	1,463,798	1,078,145
Diluted weighted average number of common shares	21,242,978	21,502,424	21,908,859	21,412,848

Consolidated Statements of Cash Flows (USD $)	9 Months Ended
Consolidated Statements of Cash Flows (USD $)	Sep. 30, 2013	Sep. 30, 2012
Operating activities
Net income	$ 2,944,149	$ 10,466,582
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation expense	834,615	722,496
Share-based compensation	393,561	628,796
Fair value adjustment of warrant liability	626,349
Changes in operating assets and liabilities:
Accounts receivable	(235,063)	(2,713,429)
Prepaid expenses	(965,815)	(69,231)
Accounts payable	(1,940,897)	(5,444,288)
Accrued expenses	(297,214)	53,860
Lease exit liability	(466,301)	(395,694)
Deferred revenue	(13,968,859)	(27,935,268)
Deferred rent	87,035	404,727
Net cash used in operating activities	(12,988,440)	(24,281,449)
Cash flows from investing activities
Purchases of property and equipment	(2,036,700)	(530,136)
Net cash used in investing activities	(2,036,700)	(530,136)
Cash flows from financing activities
Proceeds from issuance of common stock	851,183	44,309
Net cash provided by financing activities	851,183	44,309
Net change in cash and cash equivalents	(14,173,957)	(24,767,276)
Cash and cash equivalents at beginning of period	47,743,155	55,218,361
Cash and cash equivalents at end of period	$ 33,569,198	$ 30,451,085

Overview and Basis of Presentation	9 Months Ended
Overview and Basis of Presentation	Sep. 30, 2013
Accounting Policies [Abstract]
Overview and Basis of Presentation	1. Overview and Basis of Presentation MacroGenics, Inc. (the “Company”) was incorporated in Delaware on August 14, 2000. The Company is a clinical-stage biopharmaceutical company focused on discovering and developing innovative monoclonal antibody-based therapeutics for the treatment of cancer and autoimmune diseases. The Company generates its pipeline of product candidates from its proprietary suite of next-generation antibody technology platforms which it believes improve the performance of monoclonal antibodies and antibody-derived molecules. These product candidates, which the Company has identified through its understanding of disease biology and immune-mediated mechanisms, may address disease-specific challenges which are not currently being met by existing therapies. The Company creates both differentiated molecules that are directed to novel cancer targets, as well as “bio-betters” which are drugs designed to improve upon marketed medicines. The accompanying unaudited interim consolidated financial statements include the accounts of MacroGenics, Inc. and its wholly owned subsidiary, MacroGenics West, Inc. All intercompany accounts and transactions have been eliminated in consolidation. These financial statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (SEC). Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America (GAAP) have been condensed or omitted from this report, as is permitted by such rules and regulations. Accordingly, these consolidated financial statements should be read in conjunction with the financial statements and notes thereto included in the Company’s Prospectus filed with the SEC pursuant to Rule 424(b)(4) on October 11, 2013 (the Prospectus). In the opinion of the Company’s management, the consolidated unaudited interim consolidated financial statements reflect all adjustments necessary to present fairly the results of operations for the three and nine months ended September 30, 2013 and 2012, the Company’s financial position as of September 30, 2013, and the cash flows for the nine months ended September 30, 2013 and 2012. These adjustments are of a normal recurring nature. The results of operations for the three and nine months ended September 30, 2013 are not necessarily indicative of future financial results. The Company currently operates in one operating segment. Operating segments are defined as components of an enterprise about which separate discrete information is available for the chief operating decision maker, or decision making group, in deciding how to allocate resources and assessing performance. The Company views its operations and manages its business in one segment, which is developing monoclonal antibody-based therapeutics for cancer, autoimmune and infectious diseases. On October 16, 2013, the Company completed an initial public offering (IPO) of its common stock, which resulted in the sale of 5,750,000 shares, including all additional shares available to cover over-allotments, at a price of $16.00 per share. The Company received net proceeds before expenses from the IPO of $85.6 million after deducting underwriting discounts and commissions paid by the Company.

- Definition

The entire disclosure for organization, consolidation and basis of presentation of financial statements disclosure.

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+ Details

Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2013

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Use of Estimates

The preparation of the financial statements in accordance with GAAP requires the Company to make estimates and judgments in certain circumstances that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent assets and liabilities. In preparing these consolidated financial statements, management has made its best estimates and judgments of certain amounts included in the financial statements, giving due consideration to materiality. On an ongoing basis, the Company evaluates its estimates, including those related to revenue recognition, fair values of assets, convertible preferred stock and common stock, preferred stock warrant liability, income taxes, pre-clinical study and clinical trial accruals and other contingencies. Management bases its estimates on historical experience or on various other assumptions that it believes to be reasonable under the circumstances. Actual results could differ from these estimates.

In addition, through September 30, 2013, the Company utilized estimates and assumptions in determining the fair value of its common stock. The Company granted stock options at exercise prices not less than the fair value of its common stock as determined by the board of directors, with input from management. Management uses contemporaneous valuations in estimating the fair value of its common stock. The board of directors has determined the estimated fair value of the common stock based on a number of objective and subjective factors, including external market considerations affecting the biotechnology industry and the historic prices at which the Company sold shares of its preferred stock.

Cash and Cash Equivalents

The Company considers all investments in highly liquid financial instruments with an original maturity of three months or less at the date of purchase to be cash equivalents. Cash and cash equivalents consist of certificates of deposit and investment in money market funds with commercial banks and financial institutions. Cash equivalents are stated at amortized cost, plus accrued interest, which approximates fair value.

Accounts Receivable

Accounts receivable that management has the intent and ability to collect are reported in the consolidated balance sheets at outstanding amounts, less an allowance for doubtful accounts. The Company writes off uncollectible receivables when the likelihood of collection is remote.

The Company evaluates the collectability of accounts receivable on a regular basis. The allowance, if any, is based upon various factors including the financial condition and payment history of customers, an overall review of collections experience on other accounts and economic factors or events expected to affect future collections experience. No allowance was recorded as of September 30, 2013 or December 31, 2012, as the Company has a history of collecting on all outstanding accounts.

Deferred Initial Public Offering Costs

Deferred IPO costs as of September 30, 2013, consisted of legal, accounting, printing and filing fees were capitalized. The deferred costs are included in prepaid expenses on the consolidated balance sheets. The deferred offering costs were offset against the IPO proceeds received upon the completion of the offering in October 2013.

Restricted Cash

The Company is required to maintain certificates of deposit that serve as collateral for various operating leases and corporate credit card accounts. Amounts classified as restricted cash on the consolidated balance sheets are $404,850 at September 30, 2013 and December 31, 2012.

Fair Value of Financial Instruments

The fair market values of the financial instruments included in the financial statements, which include cash equivalents and money market accounts, approximate their carrying values at September 30, 2013 and December 31, 2012, due to their short-term maturities. The Company accounts for recurring and non-recurring fair value measurements in accordance with the Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) 820, Fair Value Measurements and Disclosures (ASC 820). ASC 820 defines fair value, establishes a fair value hierarchy for assets and liabilities measured at fair value, and requires expanded disclosures about fair value measurements. The ASC 820 hierarchy ranks the quality of reliability of inputs, or assumptions, used in the determination of fair value, and requires assets and liabilities carried at fair value to be classified and disclosed in one of the following three categories:

•

Level 1 – Fair value is determined by using unadjusted quoted prices that are available in active markets for identical assets and liabilities.

•

Level 2 – Fair value is determined by using inputs other than Level 1 quoted prices that are directly or indirectly observable. Inputs can include quoted prices for similar assets and liabilities in active markets or quoted prices for identical assets and liabilities in inactive markets. Related inputs can also include those used in valuation or other pricing models, such as interest rates and yield curves that can be corroborated by observable market data.

•

Level 3 – Fair value is determined by inputs that are unobservable and not corroborated by market data. Use of these inputs involves significant and subjective judgments to be made by a reporting entity – e.g., determining an appropriate adjustment to a discount factor for illiquidity associated with a given security.

The Company evaluates financial assets and liabilities subject to fair value measurements on a recurring basis to determine the appropriate level at which to classify them each reporting period. This determination requires the Company to make subjective judgments as to the significance of inputs used in determining fair value and where such inputs lie within the ASC 820 hierarchy.

Financial assets and liabilities subject to fair value measurements were as follows:


	Fair Value Measurements at September 30, 2013
	Total			Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs
	Total			Level 1		Level 2		Level 3
Assets:
Cash and cash equivalents	$	7,522,029		$	7,522,029	$	—	$	—
Money market funds		26,047,169			26,047,169		—		—
Restricted cash		404,850			404,850		—		—

Total assets	$	33,974,048		$	33,974,048	$	—	$	—

Liabilities:
Preferred stock warrant liability	$	(679,296	)	$	—	$	—	$	(679,296	)


	Fair Value Measurements at December 31, 2012
	Total			Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs
	Total			Level 1		Level 2		Level 3
Assets:
Cash and cash equivalents	$	18,695,197		$	18,695,197	$	—	$	—
Money market funds		29,047,958			29,047,958		—		—
Restricted cash		404,850			404,850		—		—

Total assets	$	48,148,005		$	48,148,005	$	—	$	—

Liabilities:
Preferred stock warrant liability	$	(52,947	)	$	—	$	—	$	(52,947	)

As of December 31, 2012, the Company transferred its money market funds from Level 2 to Level 1 because the inputs are now based upon a quoted market price.

The Company’s Level 1 securities primarily consist of restricted cash, cash equivalents and money market funds. The Company determines the estimated fair value for its Level 1 securities using quoted (unadjusted) prices for identical assets or liabilities in active markets.

The Company determines the estimated fair value for its Level 2 securities using the following methods: quoted prices for similar assets/liabilities in active markets, inputs other than quoted prices that are observable for the asset/liability (e.g., interest rates, yield curves volatilities, default rates, etc.) and inputs that are derived principally from or corroborated by other observable market data.

The following table provides a rollforward of the Company’s preferred stock warrant liability, which was the only financial instrument measured at fair value on a recurring basis using significant unobservable inputs (Level 3) as defined in ASC 820:


Balance at December 31, 2012	$	(52,947	)
Total unrealized gains (losses) included in earnings		(626,349	)

Balance at September 30, 2013	$	(679,296	)

In order to estimate the fair value of the preferred stock purchase warrants, the business enterprise value was established based on a discounted cash flow model (income approach). The Company utilized an option pricing method to value the shares using a contingent claims analysis, which applies a series of call options whose inputs reflect the liquidation preferences and conversion behavior of the different classes of equity. After the equity value of the business enterprise was determined, the total equity value is allocated to the various equity instruments such as preferred stock, stock options and preferred stock purchase warrants. Key management estimates relate to the time period to liquidation and conversion behavior of a particular class of stockholders. The business enterprise value includes assumptions related to product approval, market penetration and costs to develop the product. Significant changes to these assumptions would result in increases/decreases to the fair value of the outstanding warrants.

The total unrealized gains (losses) on the preferred stock warrants included in earnings is included as a component of other income (expense) in the consolidated statement of operations and comprehensive income.

Concentration of Credit Risk

Substantially all of the Company’s cash and cash equivalents are maintained with major financial institutions in the United States. Deposits held with banks may exceed the amount of insurance provided on such deposits. Generally, these deposits may be redeemed upon demand and, therefore, bear minimal risk.

Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash and cash equivalents, and accounts receivable. The counterparties are various corporations, financial institutions and government agencies of high credit standing.

For the three and nine months ended September 30, 2013 and 2012, all of the Company’s grant revenue was related to contracts and research grants received from U.S. government agencies. Collaborations with Les Laboratoires Servier and Institut de Recherches Servier (collectively, Servier), Boehringer Ingelheim GmbH (Boehringer), Gilead Sciences, Inc. (Gilead), Pfizer, Inc. (Pfizer) and Eli Lilly & Co. (Eli Lilly) account for all other revenue. All outstanding receivables are due from Gilead, Pfizer, Boehringer, Eli Lilly, and U.S. government agencies.

The following table represents the percentage of all significant revenue earned in the periods indicated:


	Three Months Ended September 30,						Nine Months Ended September 30,
	2013			2012			2013			2012
Servier		71.3	%		14.2	%		58.8	%		12.6	%
Boehringer		11.5	%		15.6	%		15.9	%		17.2	%
Gilead		10.9	%		0.0	%		13.7	%		0.0	%
Pfizer		4.5	%		7.7	%		7.3	%		7.4	%
Government Agencies		0.6	%		3.5	%		2.6	%		6.9	%
Eli Lilly		0.9	%		59.0	%		1.6	%		55.7	%

The following table represents the percentage of all significant accounts receivable:


	September 30, 2013			December 31, 2012
Gilead		51.2	%		—
Pfizer		22.6	%		45.4	%
Boehringer		11.1	%		18.0	%
Eli Lilly		11.0	%		28.2	%
Government Agencies		4.0	%		8.4	%

Property and Equipment

Property and equipment are stated at cost. Upon retirement or sale, the cost of assets disposed of and the related accumulated depreciation are removed from the accounts and any resulting gain or loss is credited or charged to operations. Repairs and maintenance costs are expensed as incurred. Depreciation and amortization are computed using the straight-line method over the following estimated useful lives:


Computer equipment		3 years
Software		3 years
Furniture		10 years
Laboratory and office equipment		5 years
Leasehold improvements		Shorter of lease term or useful life

Impairment of Long-Lived Assets

The Company assesses the recoverability of its long-lived assets in accordance with the provisions of ASC 360, Property, Plant and Equipment. ASC 360 requires that long-lived assets be reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of the long-lived asset is measured by a comparison of the carrying amount of the asset to future undiscounted net cash flows expected to be generated by the asset or asset group. If carrying value exceeds the sum of undiscounted cash flows, the Company then determines the fair value of the underlying asset group. Any impairment to be recognized is measured by the amount by which the carrying amount of the asset group exceeds the estimated fair value of the asset group. Assets to be disposed of are reported at the lower of the carrying amount or fair value, less costs to sell. As of September 30, 2013 and December 31, 2012, the Company determined that there were no impaired assets and had no assets held-for-sale.

Revenues

Revenue Recognition

The Company enters into collaboration and license agreements with collaborators for the development of monoclonal antibody-based therapeutics to treat cancer and other complex diseases. The terms of these agreements contain multiple deliverables which may include (i) licenses, or options to obtain licenses, to the Company’s technological platforms, such as its Fc Optimization and Dual-Affinity Re-Targeting (DART) technologies, (ii) rights to future technological improvements, (iii) research and development activities to be performed on behalf of the collaborator or as part of the collaboration, and (iv) the manufacture of pre-clinical or clinical materials for the collaborator. Payments to the Company under these agreements may include nonrefundable license fees, option fees, exercise fees, payments for research and development activities, payments for the manufacture of pre-clinical or clinical materials, license maintenance payments, payments based upon the achievement of certain milestones and royalties on product sales. Other benefits to the Company of these agreements include the right to sell products resulting from the collaborative efforts of the parties in specific geographic territories. The Company follows the provisions of the FASB ASC Topic 605-25, Revenue Recognition –Multiple-Element Arrangements, and ASC Topic 605-28, Revenue Recognition–Milestone Method, in accounting for these agreements. In order to account for these agreements, the Company must identify the deliverables included within the agreement and evaluate which deliverables represent separate units of accounting based on the achievement of certain criteria, including whether the delivered element has stand-alone value to the collaborator. The consideration received is allocated among the separate units of accounting, and the applicable revenue recognition criteria are applied to each of the separate units.

For the periods presented, the Company had the following two types of agreements with the parties identified below: 1) exclusive development and commercialization licenses to use the Company’s technology and/or certain other intellectual property to develop compounds against specified targets (referred to herein as exclusive licenses); and 2) Option/research agreements to secure on established terms, development and commercialization licenses to anticancer and other therapeutic product candidates to collaborator selected targets developed by the Company during an option period (referred to herein as right-to-develop agreements).

There are no performance, cancellation, termination or refund provisions in any of the arrangements that contain material financial consequences to the Company.

Exclusive Licenses

The deliverables under an exclusive license agreement generally include the exclusive license to the Company’s DART technology with respect to a specified antigen target, and may also include deliverables related to rights to future technological improvements, research and pre-clinical development activities to be performed on behalf of the collaborator. In some cases the Company may have an option to participate in the co-development of product candidates that result from such agreements.

Generally, exclusive license agreements contain nonrefundable terms for payments and, depending on the terms of the agreement, provide that the Company will (i) at the collaborator’s request, provide research and pre-clinical development services at negotiated prices which are generally consistent with what other third parties would charge, (ii) earn payments upon the achievement of certain milestones, (iii) earn royalty payments, and (iv) in some cases grant the Company an option to participate in the development and commercialization of products that result from such agreements. Royalty rates may vary over the royalty term depending on the Company’s intellectual property rights and whether the Company exercises any co-development and co-commercialization rights. The Company may provide technical assistance and share any technology improvements with its collaborators during the term of the collaboration agreements.

The Company does not directly control when any collaborator will achieve milestones or become liable for royalty payments.

In determining the units of accounting, management evaluates whether the exclusive license has stand-alone value from the undelivered elements to the collaborator based on the consideration of the relevant facts and circumstances for each arrangement. Factors considered in this determination include the research and development capabilities of the partner and the availability of technology platform and product research expertise in the general marketplace. If the Company concludes that the license has stand-alone value and therefore will be accounted for as a separate unit of accounting, the Company then determines the estimated selling prices of the license and all other units of accounting based on market conditions, similar arrangements entered into by third parties, and entity-specific factors such as the terms of the Company’s previous collaboration agreements, recent pre-clinical and clinical testing results of therapeutic product candidates that use the Company’s technology platforms, the Company’s pricing practices and pricing objectives, the likelihood that technological improvements will be made, the likelihood that technological improvements made will be used by the Company’s collaborators and the nature of the research services to be performed on behalf of its collaborators and market rates for similar services.

Upfront payments on exclusive licenses are deferred if facts and circumstances dictate that the license does not have stand-alone value. Prior to the adoption of Accounting Standards Update (ASU) No. 2009-13, Revenue Arrangements with Multiple Deliverables, on January 1, 2011, the Company determined that its licenses lacked stand-alone value because it did not have vendor-specific objective evidence of selling price (VSOE), and were combined with other elements of the arrangement and any amounts associated with the license were deferred and amortized over a certain period, which the Company refers to as the Company’s period of substantial involvement. In making the determination of the length of the period over which to defer revenue for contracts entered into prior to the adoption of ASU No. 2009-13, significant judgment and estimation is used by the Company and can have an impact on the amount of revenue recognized in a given period. Historically, the Company’s involvement with the development of a collaborator’s product candidate has been significant at the early stages of development, and lessens as it progresses into clinical trials. Accordingly, the Company generally estimates this period of substantial involvement to begin at the inception of the collaboration agreement and conclude at the end of the Company’s substantial involvement. ASU No. 2009-13 amends the criteria for separating and allocating consideration in a multiple element arrangement by modifying the fair value requirements for revenue recognition and eliminating the use of the residual value method. The selling prices of deliverables under an arrangement may be derived using third-party evidence (TPE), or a best estimate of selling price (BESP), if VSOE is not available. The objective of BESP is to determine the price at which the Company would transact a sale if the element within the license agreement was sold on a standalone basis. Establishing BESP involves management’s judgment and considers multiple factors, including market conditions and company-specific factors, including those factors contemplated in negotiating the agreements, as well as internally developed models that include assumptions related to market opportunity, discounted cash flows, estimated development costs, probability of success and the time needed to commercialize a product candidate pursuant to the license. In validating the BESP, management considers whether changes in key assumptions used to determine the BESP will have a significant effect on the allocation of the arrangement consideration between the multiple deliverables. Deliverables under the arrangement are separate units of accounting if (i) the delivered item has value to the customer on a standalone basis and (ii) if the arrangement includes a general right of return relative to the delivered item, delivery or performance of the undelivered item is considered probable and substantially within the Company’s control. The arrangement consideration that is fixed or determinable at the inception of the arrangement is allocated to the separate units of accounting based on their relative selling prices. The appropriate revenue recognition model is applied to each element and revenue is accordingly recognized as each element is delivered. Management exercises significant judgment in determining whether a deliverable is a separate unit of accounting.

In determining the separate units of accounting, the Company evaluated whether the exclusive license had standalone value to the collaborator based on consideration of the relevant facts and circumstances for each arrangement. Factors considered in this determination included the research and development capabilities of the collaborator and the availability of relevant research expertise in the marketplace. In addition, the Company considered whether or not (i) the collaborator could use the license for its intended purpose without the receipt of the remaining deliverables, (ii) the value of the license was dependent on the undelivered items and (iii) the collaborator or other vendors could provide the undelivered items.

The Company reassesses its periods of substantial involvement over which the Company amortizes its upfront license fees and makes adjustments as appropriate. In the event a collaborator elects to discontinue development of a specific product candidate under a single target license, but retains its right to use the Company’s technology to develop an alternative product candidate to the same target or a target substitute, the Company would cease amortization of any remaining portion of the upfront fee until there is substantial pre-clinical activity on another product candidate and its remaining period of substantial involvement can be estimated. In the event that a single target license were to be terminated, the Company would recognize as revenue any portion of the upfront fee that had not previously been recorded as revenue, but was classified as deferred revenue, at the date of such termination or through the remaining substantial involvement in the wind down of the agreement.

Upfront payments on exclusive licenses may be recognized upon delivery of the license if facts and circumstances dictate that the license has stand-alone value from the undelivered elements, which generally include rights to future technological improvements, research services and the manufacture of pre-clinical and clinical materials.

The Company recognizes revenue related to research and pre-clinical development services that represent separate units of accounting as they are performed, as long as there is persuasive evidence of an arrangement, the fee is fixed or determinable, and collection of the related receivable is probable. The Company recognizes revenue related to the rights to future technological improvements over the estimated term of the applicable license.

The Company typically performs research activities and pre-clinical development services, including generating and engineering product candidates, on behalf of its licensees during the early evaluation and pre-clinical testing stages of drug development under its exclusive licenses. The Company records amounts received for research materials produced or services performed as revenue from collaborative research.

The Company’s license agreements have milestone payments which for reporting purposes are aggregated into three categories: (i) development milestones, (ii) regulatory milestones, and (iii) sales milestones. Development milestones are typically payable when a product candidate initiates or advances into different clinical trial phases. Regulatory milestones are typically payable upon submission for marketing approval with the U.S. Food and Drug Administration (FDA) or other countries’ regulatory authorities or on receipt of actual marketing approvals for the compound or for additional indications. Sales milestones are typically payable when annual sales reach certain levels.

At the inception of each agreement that includes milestone payments, the Company evaluates whether each milestone is substantive and at risk to both parties on the basis of the contingent nature of the milestone. This evaluation includes an assessment of whether (a) the consideration is commensurate with either (1) the entity’s performance to achieve the milestone, or (2) the enhancement of the value of the delivered item(s) as a result of a specific outcome resulting from the entity’s performance to achieve the milestone, (b) the consideration relates solely to past performance and (c) the consideration is reasonable relative to all of the deliverables and payment terms within the arrangement. The Company evaluates factors such as the scientific, regulatory, commercial and other risks that must be overcome to achieve the respective milestone, the level of effort and investment required to achieve the respective milestone and whether the milestone consideration is reasonable relative to all deliverables and payment terms in the arrangement in making this assessment.

Non-refundable development and regulatory milestones that are expected to be achieved as a result of the Company’s efforts during the period of substantial involvement are considered substantive and are recognized as revenue upon the achievement of the milestone, assuming all other revenue recognition criteria are met. Milestones that are not considered substantive because the Company does not contribute effort to the achievement of such milestones are generally achieved after the period of substantial involvement and are recognized as revenue upon achievement of the milestone, as there are no undelivered elements remaining and no continuing performance obligations, assuming all other revenue recognition criteria are met.

Right-to-Develop Agreements

The Company’s right-to-develop agreements provide collaborators with an exclusive option to obtain licenses to develop and commercialize in specified geographic territories product candidates developed by the Company under agreed upon research and pre-clinical development product programs. The product candidates resulting from each program are all directed to a specific target selected by the collaborator. Under these agreements, fees may be due to the Company (i) at the inception of the arrangement (referred to as “upfront” fees or payments), (ii) the selection of a target for a program, (iii) upon the exercise of an option to acquire a development and commercialization license (referred to as exercise fees or payments earned) for a program, or (iv) some combination of all of these fees.

The accounting for right-to-develop agreements is dependent on the nature of the options granted to the collaborator. Options are considered substantive if, at the inception of a right-to-develop agreement, the Company is at risk as to whether the collaborator will choose to exercise the options to secure development and commercialization licenses. Factors that are considered in evaluating whether options are substantive include the overall objective of the arrangement, the benefit the collaborator might obtain from the agreement without exercising the options, the cost to exercise the options relative to the total upfront consideration, and the additional financial commitments imposed on the collaborator as a result of exercising the options.

For right-to-develop agreements where the options to secure development and commercialization licenses to a product program are considered substantive, the Company does not consider the development and commercialization licenses to be a deliverable at the inception of the agreement. For those right-to-develop agreements entered into prior to the adoption of ASU No. 2009-13 where the options to secure development and commercialization licenses are considered substantive, the Company has deferred the upfront payments received and recognizes this revenue over the period during which the collaborator could elect to exercise options for development and commercialization licenses. These periods are specific to each collaboration agreement. If a collaborator selects a target for a product program, any substantive option fee is deferred and recognized over the life of the option, generally 12 months. Subsequent to the adoption of ASU No. 2009-13, the Company’s evaluation of whether the option is substantive is consistent with pre-adoption of ASU No. 2009-13. How the Company determines the selling price of the option is the only difference between pre and post adoption of ASU No. 2009-13. Post adoption of ASU No. 2009-13, the selling prices of deliverables under an arrangement may be derived using TPE or a BESP, if VSOE is not available. The objective of BESP is to determine the price at which the Company would transact a sale if the element within the right-to-develop agreement was sold on a standalone basis. Establishing BESP involves management’s judgment and considers multiple factors, including market conditions and company-specific factors, including those factors contemplated in negotiating the agreements, as well as internally developed models that include assumptions related to market opportunity, discounted cash flows, estimated development costs, probability of success and the time needed to commercialize a product candidate pursuant to the right-to-develop agreement. In validating the BESP, management considers whether changes in key assumptions used to determine the BESP will have a significant effect on the allocation of the arrangement consideration between the multiple deliverables. Deliverables under the arrangement are separate units of accounting if (i) the delivered item has value to the customer on a standalone basis and (ii) if the arrangement includes a general right of return relative to the delivered item, delivery or performance of the undelivered item is considered probable and substantially within the Company’s control. The arrangement consideration that is fixed or determinable at the inception of the arrangement is allocated to the separate units of accounting based on their relative selling prices. The appropriate revenue recognition model is applied to each element and revenue is accordingly recognized as each element is delivered. Management exercises significant judgment in determining whether a deliverable is a separate unit of accounting.

If a collaborator exercises an option and acquires a development and commercialization license to a product program, the Company attributes the exercise fee to the development and commercialization license. The Company determines the selling price of the option license, upon exercise, through management’s best estimate. Management’s determination of selling price includes such factors as stage of development, market potential and cash flow models used during the negotiation with the collaborator. There have been no option license exercises to date for any period presented. Upon exercise of an option to acquire a development and commercialization license, the Company would also attribute any remaining deferred option fee to the development and commercialization license and apply the multiple-element revenue recognition criteria to the development and commercialization license and any other deliverables to determine the appropriate revenue recognition, which will be consistent with the Company’s accounting policy for upfront payments on exclusive licenses event a right-to-develop agreement were to be terminated, the Company would recognize as revenue any portion of the upfront fee that had not previously been recorded as revenue, but was classified as deferred revenue, at the date of such termination. The Company’s right-to-develop agreements have been determined to contain substantive options.

For right-to-develop agreements where the options to secure development and commercialization licenses to product programs are not considered substantive, the Company considers the development and commercialization licenses to be a deliverable at the inception of the agreement and applies the multiple-element revenue recognition criteria to determine the appropriate revenue recognition. The Company does not directly control when any collaborator will exercise its options for development and commercialization licenses.

Research and Development Costs

Research and development expenditures are expensed as incurred. Research and development costs primarily consist of employee related expenses, including salaries and benefits, expenses incurred under agreements with contract research organizations, investigative sites and consultants that conduct the Company’s clinical trials, the cost of acquiring and manufacturing clinical trial materials and other allocated expenses, license fees for and milestone payments related to in-licensed products and technologies, stock-based compensation expense, and costs associated with non-clinical activities and regulatory approvals.

Comprehensive Income (Loss)

Effective January 1, 2012, the Company adopted ASU2011-05, Presentation of Comprehensive Income, which amended ASC Topic 220, Comprehensive Income. The amendments in ASU 2011-05 require the presentation of the comprehensive income (loss) and its components as part of the consolidated financial statements. Comprehensive income (loss) is comprised of the net income (loss) and other changes in equity that are excluded from net income (loss). Comprehensive income (loss) equals net income (loss) for the three and nine months ended September 30, 2013 and 2012.

Stock-based Compensation

Stock-based payments are accounted for in accordance with the provisions of ASC 718, Compensation – Stock Compensation. The fair value of stock-based payments is estimated, on the date of grant, using the Black-Scholes model. The resulting fair value is recognized ratably over the requisite service period, which is generally the vesting period of the option.

For all time-vesting awards granted, expense is amortized using the straight-line attribution method. For awards that contain a performance condition, expense is amortized using the accelerated attribution method. Recognition of stock-based compensation expense is based on the value of the portion of stock-based awards that is ultimately expected to vest during the period.

The Company utilizes the Black-Scholes model for estimating fair value of its stock options granted. Option valuation models, including the Black-Scholes model, require the input of highly subjective assumptions, and changes in the assumptions used can materially affect the grant-date fair value of an award. These assumptions include the risk-free rate of interest, expected dividend yield, expected volatility and the expected life of the award.

Net Income (Loss) Per Share

Income (loss) per share is calculated under the two-class method under which all earnings (distributed and undistributed) are allocated to each class of common stock and participating securities based on their respective rights to receive dividends. In the event that the Board of Directors shall declare a dividend payable in cash or other property on the then-outstanding shares of common stock, the holders of the Series A-1, A-2, B, C, D, and D-2 convertible preferred stock shall be entitled to receive the amount of dividends per share of Preferred Stock that would be payable on the largest number of whole shares of Common Stock into which each share of Preferred Stock could then be converted. Therefore, the Series A-1, A-2, B, C, D and D-2 are participating securities.

Basic net income (loss) per common share is determined by dividing the net income (loss) allocable to common stockholders by the weighted-average number of common shares outstanding during the period, without consideration of common stock equivalents. Diluted net income (loss) per share is computed by dividing the net income (loss) allocable to common stockholders by the weighted-average number of common stock equivalents outstanding for the period. The treasury stock method is used to determine the dilutive effect of the Company’s stock option grants and the if-converted method is used to determine the dilutive effect of the Company’s Series A-1, A-2, B, C, D, and D-2 convertible preferred stock.

Basic and diluted income (loss) per common share is computed as follows:


	Three Months Ended September 30,						Nine Months Ended September 30,
	2013			2012			2013			2012
Net income (loss)	$	6,603,982		$	2,600,514		$	2,944,149		$	10,466,582
Less: undistributed earnings allocated to participating securities		(6,434,756	)		(2,600,514	)		(2,944,149	)		(10,466,582	)

Net income (loss) allocable to common shares	$	169,226		$	—		$	—		$	—

Basic weighted average common shares outstanding		1,184,507			1,092,307			1,463,798			1,078,145
Basic income (loss) per common share	$	0.14		$	—		$	—		$	—
Net income (loss)	$	6,603,982		$	2,600,514		$	2,944,149		$	10,466,582
Less: undistributed earnings allocated to participating securities and other add-backs to net income (loss)		(6,403,843	)		(2,600,514	)		(2,944,149	)		(10,466,582	)

Net income (loss) allocable to common shares	$	200,139		$	—		$	—		$	—

Basic weighted average common shares outstanding		1,184,507			1,092,307			1,463,798			1,078,145
Effect of dilutive securities		20,058,471			20,410,117			20,445,061			20,334,703

Diluted weighted average common shares outstanding		21,242,978			21,502,424			21,908,859			21,412,848

Diluted income (loss) per common share	$	0.01		$	—		$	—		$	—

The following common stock equivalents are included in the calculation of diluted net income (loss) per share:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2013		2012		2013		2012
Series A-1 Preferred Stock		2,156,114		2,156,114		2,156,114		2,156,114
Series A-2 Preferred Stock		392,274		392,274		392,274		392,274
Series B Preferred Stock		4,336,037		4,336,037		4,336,037		4,336,037
Series C Preferred Stock		5,909,906		5,909,906		5,909,906		5,909,906
Series D Preferred Stock		769,468		769,468		769,468		769,468
Series D-2 Preferred Stock		3,391,991		3,391,991		3,391,991		3,391,991
Warrants to purchase Series D-2 Preferred Stock		180,784		180,784		180,784		180,784
Stock Options		2,910,952		3,276,516		2,910,952		3,276,516

Recently Issued Accounting Standards Adopted

In May 2011, the FASB issued ASU No. 2011-04, which amended ASC Topic 820 to achieve common fair value measurements and disclosure requirements in U.S. GAAP and International Financial Reporting Standards (IFRS). The amendments in ASU No. 2011-04 result in common fair value measurement and disclosure requirements in U.S. GAAP and IFRS. Consequently, the amendments change the wording used to describe many of the requirements in U.S. GAAP for measuring fair value and for disclosing information about fair value measurements. This amendment is effective for fiscal years beginning after December 15, 2011. The adoption of this amendment did not have a material impact on the Company’s consolidated financial statements.

In June 2011, the FASB issued ASU No. 2011-05, which amended ASC Topic 220 regarding presentation of comprehensive income. The amendments in ASU No. 2011-05 require that all nonowner changes in stockholders’ equity be presented either in a single continuous statement of comprehensive income or in two separate but consecutive statements. In the two-statement approach, the first statement should present total net income and its components followed consecutively by a second statement that should present total other comprehensive income, the components of other comprehensive income, and the total of comprehensive income. This amendment is effective for fiscal years beginning after December 15, 2011. The adoption of this amendment did not have a material impact on the Company’s consolidated financial statements.

The Company has evaluated all ASUs through the date the consolidated financials were issued and believes that the adoption of these will not have a material impact on the Company’s consolidated financial statements.

- Definition

The entire disclosure for all significant accounting policies of the reporting entity.

+ References+ Details

Property and Equipment

9 Months Ended

Sep. 30, 2013

Property Plant And Equipment [Abstract]

Property and Equipment

3. Property and Equipment

Property and equipment consists of the following:


	September 30, 2013			December 31, 2012
Computer equipment	$	2,172,535		$	2,003,706
Software		1,323,081			1,323,081
Furniture		599,650			599,650
Lab equipment		10,603,598			8,747,790
Office equipment		51,360			51,360
Leasehold improvements		4,893,770			4,881,706

Property and equipment		19,643,994			17,607,293
Less accumulated depreciation and amortization		(15,174,112	)		(14,339,497	)

Property and equipment, net	$	4,469,882		$	3,267,796

Depreciation and amortization expense for the three months ended September 30, 2013 and 2012 was $316,852 and $235,543, respectively, and $834,615 and $722,496 for the nine months ended September 30, 2013 and 2012, respectively.

- Definition

The entire disclosure for long-lived, physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, accounting policies and methodology, roll forwards, depreciation, depletion and amortization expense, including composite depreciation, accumulated depreciation, depletion and amortization expense, useful lives and method used, income statement disclosures, assets held for sale and public utility disclosures.

+ References+ Details

Stockholders' Equity (Deficit)	9 Months Ended
Stockholders' Equity (Deficit)	Sep. 30, 2013
Equity [Abstract]
Stockholders' Equity (Deficit)	4. Stockholders’ Equity (Deficit) During 2002 and 2003, the Company issued a total of 34,239,374 shares of Series A-1 and Series A-2 convertible preferred stock (Series A preferred stock) for $1.00 per share resulting in net proceeds of approximately $34,000,000. On October 12, 2004, the Company entered into a series of transactions raising $30,261,672, net of related offering costs of approximately $238,000, from the sale of 71,401,237 shares of its Series B convertible preferred stock (Series B preferred stock). In connection with the Series B preferred stock offering, 13,604,016 shares of common stock were allocated to holders of Series A-1 preferred stock as an anti-dilution measure but remained unissued at September 30, 2013. Upon completion of the IPO in October 2013, these allocated shares were converted into shares of common stock. On May 16, 2006, the Company raised $44,898,754, net of related offering costs of $101,246, from the sale of 110,952,217 shares of its Series C convertible preferred stock (Series C preferred stock). In connection with the Series C preferred stock offering, 10,003,300 shares of common stock were allocated to holders of Series B preferred stock as an anti-dilution measure but remained unissued at September 30, 2013. Upon completion of the IPO in October 2013, these allocated shares were converted into shares of common stock. On July 16, 2008, the Company issued 12,466,039 shares of its Series D convertible preferred stock (Series D preferred stock) in exchange for all of the outstanding capital stock and convertible notes payable of Raven Biotechnologies, Inc. (Raven). Subsequently, in March 2011 a settlement was reached with the former Raven stockholders bringing the total Series D preferred stock issued in connection with the Raven acquisition to 14,446,227 shares. On September 19, 2008, the Company raised $24,843,211, net of related offering costs of $156,788, from the sale of 38,337,678 shares of its Series D-2 convertible preferred stock (Series D-2 preferred stock). The Company also issued preferred stock warrants for the purchase of 2,875,327 shares of Series D-2 preferred stock. The preferred stock warrants are exercisable at any time prior to September 2018, but expire upon an IPO, and have a stated exercise price of $0.65 per warrant. On May 16, 2010, the Company exercised a put notice to Lilly in accordance with the Series D-2 preferred stock purchase agreement, resulting in the issuance of 6,916,110 shares of Series D-2 preferred stock and a warrant to purchase 518,708 additional shares of Series D-2 preferred stock. On January 11, 2011, the Company raised gross proceeds for $12,016,500 from the sale of 18,427,388 shares of its Series D-2 preferred stock. Issuance costs associated with the sale were not material. Due to certain provisions in the Series D-2 convertible preferred stock warrant agreement, these warrants are required to be classified as a liability. Management believes that the circumstances requiring cash settlement of the award are remote. The Series D-2 preferred stock warrant liability is recorded at fair value, which is adjusted at the end of each reporting period using the Option-Pricing Method, with changes in value recorded as “Other income (expense)” in the accompanying consolidated statements of operations. Holders of the Series A-1, Series A-2, Series B, Series C, Series D and Series D-2 preferred stock are entitled to vote, together with the common stockholders as one class, on all matters as to which common stockholders are entitled to vote. In any such vote, each share of Series A, Series B, Series C and Series D preferred stock shall entitle the holder to the number of votes per share that equals the number of shares of common stock into which each such share of preferred stock is then convertible. For so long as at least four million shares of each of the Series A, Series B and Series C preferred stock remain outstanding, the holders of each of the Series A, Series B and Series C preferred stock, each voting as a separate class, shall each be entitled to elect two members of the Board of Directors of the Company. The holders of a majority of the common stock, voting as a separate class, shall have the right to elect one member of the Board of Directors of the Company. The holders of a majority of the common stock and the holders of at least 66 2/3% of the preferred stock, each voting separately as a single class (and on an as-if-converted basis to common stock with respect to the preferred stock), shall be entitled to elect all remaining members of the Board of Directors. Dividends are noncumulative and accrue on the Series A-1, Series A-2, Series B, Series C, Series D and Series D-2 preferred stock at a rate of $0.08, $0.0341, $0.0324 and $0.0522 per annum, respectively, and are payable when and as declared by the Board of Directors. Dividends must be declared so that the Series A, Series B, Series C and Series D preferred stock are paid in like-kind and participate equally to those of the Series D-2 preferred and common stock. No dividends have been declared and none are accrued at September 30, 2013 or December 31, 2012. The Company’s Series A-1, Series A-2, Series B, Series C, Series D and Series D-2 preferred stock are initially convertible into 1.506, 1.00, 1.14, 1.00, 1.00 and 1.00 shares, respectively, of common stock at the option of the holder. The conversion ratio of certain series of preferred stock is subject to change in the event specified dilutive transactions occur. These dilutive events are considered to be the sale of common stock at a per share price less than the applicable preferred stock conversion price. There are no anti-dilution protections for the Series A-2 preferred stock and no adjustment to the Series A-1 preferred stock conversion price is made if a common stock issuance is at a price per share greater than the conversion price of the Series C preferred stock. The conversion price shall be $12.39, $18.77, $6.95, $7.70, $12.20 and $12.20 for each share of Series A-1, A-2, Series B, Series C, Series D and Series D-2 convertible preferred stock, respectively. The Company has reserved 17,129,782 shares of common stock for the potential conversion of the Series A-1, Series A-2, Series B, Series C, Series D and Series D-2 preferred stock. Each share of Series A-1, Series A-2, Series B, Series C, Series D and Series D-2 preferred stock automatically converts into shares of the Company’s common stock upon closing of a firm commitment underwritten public offering of common stock registered under the Securities Act of 1933 which generates net proceeds to the Company of at least $40 million. The holders of two-thirds of the Series A-1, Series A-2, Series B, Series C, Series D and Series D-2 preferred stock, voting together as a single class, but separately from the common stockholders, shall have the right to elect to convert all outstanding shares of Series A-1, Series A-2, Series B, Series C, Series D and Series D-2 preferred stock into shares of common stock. In liquidation, the holders of Series D-2 preferred stock are entitled to receive $12.20 per share prior to any distribution to the holders of any Series C and Series D preferred stock. The holders of Series C and Series D preferred stock are entitled to receive $7.70 and $12.20 per share, respectively, on a pari passu basis, prior to any distribution to the holders of any Series B preferred stock. The holders of Series B preferred stock are entitled to receive $6.95 per share prior to any distribution to the holders of any shares of Series A preferred stock. The holders of Series A preferred stock are entitled to receive $12.39 per share prior to the holders of common stock. In connection with preparing for its IPO in October 2013 (see Note 11, Subsequent Events, for additional information), the Company’s Board of Directors and stockholders approved a 1-for-18.7739 reverse stock split of the Company’s Common Stock. The reverse stock split became effective on September 26, 2013. All share and per share amounts in the consolidated financial statements and notes thereto have been retroactively adjusted for all periods presented to give effect to this reverse stock split, including reclassifying an amount equal to the reduction in par value of common stock to additional paid-in capital. In addition, in September 2013, the Company’s Board of Directors and stockholders approved an amendment of the Company’s certificate of incorporation to, among other things, change the definition of a designated public offering to remove the per share price requirement.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29-31)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30, 31

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 4.E)

-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74512-122707

Reference 5: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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+ Details

Shared-Based Payments

9 Months Ended

Sep. 30, 2013

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Shared-Based Payments

5. Shared-Based Payments

Stock Option Plan

The Company’s 2000 Stock Option and Incentive Plan (the 2000 Plan) allowed for the grant of awards in respect of an aggregate of 130,725 shares, which was increased to 150,297 shares, of the Company’s common stock in the form of incentive stock options, non-qualified stock options, stock appreciation rights, restricted stock and restricted stock units and other performance awards.

Effective February 2003, the Company implemented the 2003 Equity Incentive Plan (the 2003 Plan), and it was amended and approved by the Company’s stockholders in 2005. The 2003 Plan originally allowed for the grant of awards in respect of an aggregate of 2,051,644 shares of the Company’s common stock. During the year ended December 31, 2006, the maximum number of shares of common stock authorized to be issued by the Company under the 2003 Plan was increased by 460,746 shares to 2,512,390. During the year ended December 31, 2008, the maximum number of shares of common stock authorized to be issued by the Company under the 2003 Plan was increased by 745,716 shares to 3,258,106. During the year ended December 31, 2010, the maximum number of shares of common stock authorized to be issued by the Company under the 2003 Plan was increased by 532,654 shares to 3,790,760. During the year ended December 31, 2012, the maximum number of shares of common stock authorized to be issued by the Company under the 2003 Plan was increased by 545,970 shares to 4,336,731. As of September 30, 2013, a total of 8,171 shares were available for issuance under the 2003 Plan.

Stock options granted under the 2003 Plan may be either incentive stock options as defined by the Internal Revenue Code (IRC), or non-qualified stock options.

The following stock-based compensation amounts were recognized for the periods indicated:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2013		2012		2013		2012
Research and development	$	111,888	$	117,952	$	284,281	$	353,856
General and administrative		24,048		91,647		109,280		274,940

Total stock-based compensation expense	$	135,936	$	209,599	$	393,561	$	628,796

Employee Stock Options

The fair value of each option award is estimated on the date of grant using the Black-Scholes option-pricing model using the assumptions in the following table:


	Nine Months Ended September 30,
	2013	2012
Expected dividend yield	0%	0%
Expected volatility	53% - 58%	51%
Risk-free interest rate	1.24% - 2.05%	1.18%
Expected average life of options	7 years	7 years
Fair market value of common stock at:	$1.50 - $7.51	$1.50
Expected forfeiture rate	5.06%	5.57%

Fair Value of Common Stock – Before our entry into the public market on October 10, 2013, the Company’s Board of Directors determined the fair value of the common stock. The Board of Directors made determinations of fair value based, in part, upon contemporaneous valuations to determine fair value. In the absence of a public market, and as a clinical-stage company with no significant revenues, the Company believes that it is appropriate to consider a range of factors to determine the fair market value of the common stock at each grant date. The factors include: (1) the achievement of clinical and operational milestones by the Company; (2) the status of strategic relationships with collaborators; (3) the significant risks associated with the Company’s stage of development; (4) capital market conditions for life science companies, particularly similarly situated, privately held, early-stage life science companies; (5) the Company’s available cash, financial condition and results of operations; (6) the most recent sales of the Company’s preferred stock and (7) the preferential rights of the outstanding preferred stock. The contemporaneous valuations were performed in accordance with applicable methodologies, approaches and assumptions of the technical practice-aid issued by the American Institute of Certified Public Accountants Practice Aid entitled Valuation of Privately-Held Company Equity Securities Issued as Compensation.

Expected Volatility – Volatility is a measure of the amount by which a financial variable such as a share price has fluctuated (historical volatility) or is expected to fluctuate (expected volatility) during a period. The Company does not maintain an internal market for its shares and its shares are not traded publicly. The Company has been able to identify several public entities of similar size, complexity and stage of development; accordingly, historical volatility has been calculated using the volatility of these companies.

Expected Dividend Yield – The Company has never declared or paid dividends and has no plans to do so in the foreseeable future.

Risk-Free Interest Rate – This is the U.S. Treasury rate for the week of each option grant during the year, having a term that most closely resembles the expected life of the option.

Expected Term – This is the period of time that the options granted are expected to remain unexercised. Options granted have a maximum term of ten years. The Company estimates the expected life of the option term to be seven years. The Company uses a simplified method to calculate the average expected term.

Expected Forfeiture Rate – The forfeiture rate is the estimated percentage of options granted that is expected to be forfeited or canceled on an annual basis before becoming fully vested. The Company estimates the forfeiture rate based on turnover data with further consideration given to the class of the employees to whom the options were granted.

Equity instruments issued to non-employees are accounted for under the provisions of ASC 505-50, Equity Based Payments to Non-Employees. Accordingly, the estimated fair value of the equity instrument is recorded on the earlier of the performance commitment date or the date the services required are completed.

The following table summarizes stock option activity under the Plan during the period then ended:


	Number of Options			Weighted- Average Exercise Price		Weighted- Average Contractual Term (in Years)
Outstanding, December 31, 2012		3,249,702			0.94		7.3
Granted		687,183			3.19		7.0
Exercised		(1,025,933	)		0.75
Forfeited or expired		(33,949	)		1.13

Outstanding, September 30, 2013		2,877,003			1.50		7.2

September 30, 2013:
Exercisable		1,855,178			0.94
Vested and Expected to Vest		918,600			2.44

The aggregate intrinsic value of options outstanding and options exercisable as of September 30, 2013 is approximately $17.4 million and $12.2 million, respectively.

The weighted-average grant-date fair value of options granted for the nine months ended September 30, 2013 was $2.00. Total cash received for the options exercised was $851,183 for the nine months ended September 30, 2013. The total fair value of shares vested in the nine months ended September 30, 2013 was $402,084. As of September 30, 2013, the total unrecognized compensation expense related to non-vested stock-based compensation arrangements granted under the 2000 Plan and 2003 Plan, net of related forfeiture estimates, was $1.5 million, which the Company expects to recognize over a weighted-average period of approximately four years.

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References+ Details

Lease Exit Liability

9 Months Ended

Sep. 30, 2013

Restructuring And Related Activities [Abstract]

Lease Exit Liability

6. Lease Exit Liability

On July 16, 2008, the Company acquired Raven Biotechnologies, Inc. (Raven), a private South San Francisco-based company focused on the development of monoclonal antibody therapeutics for treating cancer. Raven was considered a development-stage enterprise as defined in ASC 915, Development Stage Entities. In connection with the acquisition, the Company issued 12,466,039 shares of its Series D convertible preferred stock in exchange for all of the outstanding capital stock and convertible notes payable of Raven.

The Company undertook restructuring activities related to the acquisition of Raven. These restructuring activities included reductions in staffing levels and the intended exit of leased facilities. All severance-related payments were completed in the year ended December 31, 2009.

In connection with these restructuring activities, as part of the cost of acquisitions, the Company established a restructuring liability attributed to an existing operating lease. The terms of the operating lease extend through 2018.

Changes in the lease exit liability are as follows:


Accrual balance at December 31, 2011	$	10,607,499
Principal payments		(533,560	)

Accrual balance at December 31, 2012		10,073,939
Principal payments		(466,301	)

Accrual balance at September 30, 2013	$	9,607,638

Future principal payments to be made under the lease agreement for the next five years and thereafter as of September 30, 2013 are as follows:


Twelve Months Ending September 30,
2014	$	1,229,454
2015		1,589,410
2016		1,808,119
2017		2,049,273
2018		2,315,026
Thereafter		616,356

	$	9,607,638

The purchase agreement provides for a specified total of certain contingent milestones that are based on the achievement of certain product sales derived from the acquired Raven technology. Also, a onetime payment of $5.0 million will be made to the Raven stockholders upon the initiation of patient dosing in the first Phase 2 clinical trial of any product derived from the Raven “Cancer Stem Cell Program.” No payment shall be made if the Phase 2 trial start date has not occurred on or before July 15, 2018. Other consideration includes a percentage of revenue (excluding consideration for research and development and equity) received by MacroGenics for license of a product derived from the Raven “Cancer Stem Cell Program” and a onetime payment ranging from $8.0 million to $12.0 million dependent upon a specified level of sales of products derived from the Raven “Cancer Stem Cell Program.”

The contingent consideration will be accounted for as additional purchase price and recorded as incremental in-process research and development expense when it is deemed probable that the contingencies will be attained. No additional amounts have been recorded during the nine months ended September 30, 2013 and 2012.

- Definition

The entire disclosure for restructuring and related activities. Description of restructuring activities such as exit and disposal activities, include facts and circumstances leading to the plan, the expected plan completion date, the major types of costs associated with the plan activities, total expected costs, the accrual balance at the end of the period, and the periods over which the remaining accrual will be settled.

+ References+ Details

Collaboration and License Agreements	9 Months Ended
Collaboration and License Agreements	Sep. 30, 2013
Text Block [Abstract]
Collaboration and License Agreements	7. Collaboration and License Agreements *Les Laboratoires Servier* In November 2011, the Company entered into a right-to-develop collaboration agreement with Servier for the development and commercialization of MGA271 in all countries other than the United States, Canada, Mexico, Japan, South Korea and India. Upon execution of the agreement, Servier made a nonrefundable payment of $20 million to the Company. The Company is eligible to receive up to $30 million in license grant fees, $47 million in clinical milestone payments, $140 million in regulatory milestone payments and $208 million in sales milestone payments if Servier exercises the option, obtains regulatory approval for and successfully commercializes MGA271. The Company concluded that the license grant fees are not deliverables at the inception of the arrangement. The Company has determined that each potential future clinical, development and regulatory milestone is substantive. Although sales milestones are not considered substantive, they are still recognized upon achievement of the milestone (assuming all other revenue recognition criteria have been met) because there are no undelivered elements that would preclude revenue recognition at that time. In the event Servier exercises its option to continue development of MGA271, Servier must pay a license grant fee. Under this agreement, Servier would be obligated to pay the Company from low double digit to mid-teen royalties on product sales in its territories. The Company has evaluated the research collaboration agreement with Servier and has determined that it is a revenue arrangement with multiple deliverables, or performance obligations. The Company concluded that the option is substantive and that the license fees for this option is not a deliverable at the inception of the arrangement as there is considerable uncertainty that the option would be exercised and the additional fee to be paid upon exercise of the option represents its estimated selling price (i.e. no substantial discount was given). The Company’s substantive performance obligations under this research collaboration include an exclusivity clause to its technology, technical, scientific and intellectual property support to the research plan during the first year of the agreement and participation on an executive committee and a research and development committee. The Company determined that these performance obligations represent a single unit of accounting, since the license does not have stand-alone value to Servier without the Company’s technical expertise and committee participation. As such, the initial upfront payment was deferred and is being recognized ratably over the initial 27-month period, which represents the expected period of development and the Company’s participation on the research and development committee. The Company further concluded that each potential future clinical, development and regulatory milestone is substantive. During the three months ended September 30, 2013 and 2012 the Company recognized revenue of $12.3 million (including a $10.0 million milestone payment) and $2.3 million, respectively. During the nine months ended September 30, 2013 and 2012 the Company recognized revenue of $18.9 million (including a $10.0 million milestone payment) and $6.8 million, respectively, under this agreement. At September 30, 2013, $3.1 million of revenue was deferred under this agreement, all of which was included in current liabilities. At December 31, 2012, $10.0 million of revenue was deferred under this agreement, $9.1 million of which was included in current liabilities and $0.9 million was included in long-term liabilities. In September 2012, the Company entered into a second right-to-develop collaboration agreement with Servier and granted it options to obtain three separate exclusive licenses to develop and commercialize DART-based molecules, consisting of those designated by the Company as MGD006 and MGD007, as well as a third DART molecule, in all countries other than the United States, Canada, Mexico, Japan, South Korea and India. Upon execution of the agreement, Servier made a nonrefundable payment of $20 million to the Company. In addition, the Company will be eligible to receive up to $65 million in license grant fees, $98 million in clinical milestone payments, including $5 million upon IND acceptance for each of MGD006, MGD007 and a third DART molecule, $300 million in regulatory milestone payments and $630 million in sales milestone payments if Servier exercises all of the options and successfully develops, obtains regulatory approval for, and commercializes a product under each license. In addition to these milestones, the Company and Servier will share Phase 2 and Phase 3 development costs. The Company has determined that each potential future clinical, development and regulatory milestone is substantive. Although sales milestones are not considered substantive, they are still recognized upon achievement of the milestone (assuming all other revenue recognition criteria have been met) because there are no undelivered elements that would preclude revenue recognition at that time. Under this agreement, Servier would be obligated to pay the Company between high-single digit and mid-teen royalties on net product sales in its territories. The Company has evaluated the research collaboration agreement with Servier and has determined that it is a revenue arrangement with multiple deliverables, or performance obligations. The Company concluded that each option is substantive and that the license fees for each option are not deliverables at the inception of the arrangement and were not issued with a substantial discount. The Company’s substantive performance obligations under this research collaboration include an exclusivity clause to its technology, technical, scientific and intellectual property support to the research plan during the first year of the agreement and participation on an executive committee and a research and development committee. The Company determined that the performance obligations with respect to the pre-clinical development represent a single unit of accounting, since the license does not have stand-alone value to Servier without the Company’s technical expertise and committee participation. As such, the initial up front license payment was deferred and is being recognized ratably over the initial 29-month period, which represents the expected development period. The Company further concluded that each potential future clinical, development and regulatory milestone is substantive. During the three and nine months ended September 30, 2013 the Company recognized revenue of $2.2 million and $6.5 million, respectively. No revenue was recognized under this agreement during the comparable periods in 2012. No milestones have been recognized under this agreement during the three and nine months ended September 30, 2013. At September 30, 2013, $11.6 million of revenue was deferred under this agreement, $8.6 million of which was included in current liabilities and $3.0 million of which was included in long-term liabilities. At December 31, 2012, $18.0 million of revenue was deferred under this agreement, $8.6 million of which was included in current liabilities and $9.4 million of which was included in long-term liabilities. *Gilead Sciences, Inc.* In January 2013, the Company entered into an agreement with Gilead to grant it an exclusive worldwide license to research, develop and commercialize up to four DART-based molecules. Gilead has exclusive worldwide rights for three of the programs. For one program, the Company retains development and commercialization rights outside of North America, the European Union, Norway, Iceland, Turkey, Australia and New Zealand. The Company received an initial $7.5 million license grant fee for the first DART-based molecule. The Company may be eligible to receive additional license grant fees of $22.5 million, $200 million related to pre-clinical and clinical milestones, $355 million related to regulatory milestones and $500 million related to sales milestones if Gilead exercises all four of the options and successfully develops, obtains regulatory approval for, and commercializes a product under each option and license. The Company has determined that the other licenses are conditional deliverables, which are substantive options that were not granted with a substantial discount. The Company has determined that each potential future clinical, development and regulatory milestone is substantive. Although sales milestones are not considered substantive, they are still recognized upon achievement of the milestone (assuming all other revenue recognition criteria have been met) because there are no undelivered elements that would preclude revenue recognition at that time. Gilead also provides funding for the Company’s internal and external research costs under the agreement. Additionally, Gilead would be obligated to pay the Company high single digit to low double digit, but less than teen royalties on product sales in its territories. The Company has evaluated the research collaboration agreement with Gilead and has determined that it is a revenue arrangement with multiple deliverables, or performance obligations. The Company’s substantive performance obligations under this research collaboration include a license to its technology and research and development services. The Company concluded that the deliverables do not have stand alone value and therefore, represent a combined single unit of accounting. Due to the lack of standalone value for the license and research and development services, the combined unit of accounting (the upfront payment and the expected research and development reimbursements) is being recognized ratably over a period of 21 months, which represents the expected development period. The Company and Gilead have also agreed to establish a joint research committee to facilitate the governance and oversight of the parties’ activities under the agreements. Management considered whether participation on the joint committee may be a deliverable and determined that it was not a deliverable. Had management considered participation on the joint committee as a deliverable, it would not have had a material impact on the accounting for the arrangement. Receivables of $1.1 million as of September 30, 2013 relate to amounts due to the Company from Gilead for reimbursement work performed under the collaboration. The Company recognized revenues of approximately $2.2 million and $5.9 million under this agreement for the three and nine months ended September 30, 2013, respectively. No milestones have been reached under this agreement. At September 30, 2013, $4.4 million of revenue was deferred under this agreement, all of which was included in current liabilities. *Boehringer Ingelheim International GmbH* In October 2010 the Company entered into a collaboration and license agreement with Boehringer to discover, develop and commercialize up to ten DART-based molecules which span multiple therapeutic areas. Under the terms of the agreement, the Company granted Boehringer an exclusive, worldwide, royalty-bearing, license under its intellectual property to research, develop, and market DARTs generated under the agreement, or the Boehringer licensed products, throughout the world. Upon execution of the agreement, the Company received an upfront payment of $15 million. The Company subsequently received two annual maintenance payments and anticipates receiving a third annual maintenance payment in the fourth quarter of 2013. The first two maintenance payments were solely attributed to the passage time. Because Boehringer has the option to cancel the program after the second anniversary of the agreement, the third maintenance payment will be recognized over the remaining obligation period once received. The Company has the potential to earn milestone payments of approximately $41 million related to pre-clinical and clinical development, $89 million related to regulatory milestones and $83 million related to sales milestones for each of the DART programs under this agreement in the case of full commercial success of multiple DART products. The Company has determined that each potential future clinical, development and regulatory milestone is substantive. Although sales milestones are not considered substantive, they are still recognized upon achievement of the milestone (assuming all other revenue recognition criteria have been met) because there are no undelivered elements that would preclude revenue recognition at that time. Boehringer also provides funding for the Company’s internal and external research costs and is required to pay the Company mid-single digit royalties on product sales. From the commencement of the collaboration through September 30, 2013, the Company has received $39.0 million under this agreement, including upfront, annual maintenance and milestone payments as well as research funding. In addition, Boehringer purchased $10 million of the Company’s Series D-2 Preferred Stock in January 2011. The Company determined that the deliverables under the Boehringer agreement include the license, the research and development services to be performed by the Company, and the co-promotion/manufacturing services. The Company concluded that the co-promotional activities were optional and were subject to further negotiation upon reaching regulatory approval. As such, the co-promotional period is not included in the expected obligation period to perform services. The Company concluded that the undelivered element of research and development services had fair value. The Company concluded that the license does not have value on a standalone basis (e.g. absent the provision of the research and development services) and therefore does not represent a separate unit of accounting. The Company concluded that because the drug candidate has not yet been developed, the license is of no value to Boehringer without the ensuing research and development activities using the DART technology, which is proprietary to the Company. Likewise, Boehringer could not sell the license to another party (without the Company agreeing to provide the research and development activities for the other party). Therefore, the upfront license fee and research and development services were treated as a combined unit of account and recognized over the expected obligation period associated with the research and development services through September 2015, which represents the estimated period of development. The Company and Boehringer have also agreed to establish a joint research committee to facilitate the governance and oversight of the parties’ activities under the agreements. Management considered whether participation on the joint committee may be a deliverable and determined that it was not a deliverable. However, had management considered participation on the joint committee as a deliverable, it would not have had a material impact on the accounting for the arrangement as the period of participation in this committee matched the organization period for the research and development services. There have been no material modifications to this agreement since the adoption of ASU 2009-13 on January 1, 2011. Receivables of $246,375 and $355,568 as of September 30, 2013 and December 31, 2012, respectively, relate to amounts due to the Company from Boehringer for reimbursement work performed under the collaboration. The Company recognized revenues of approximately $2.3 million and $2.5 million under this agreement during the three months ended September 30, 2013 and 2012, respectively, and $6.9 million and $9.3 million during the nine months ended September 30, 2013 and 2012, respectively. One milestone payment of $2.0 million was recognized under this agreement through December 2012. No milestones have been recognized under this agreement during the three and nine months ended September 30, 2013. A milestone was earned under this agreement subsequent to September 30, 2013. See Note 11, Subsequent Events, for additional information. At September 30, 2013, $10.3 million of revenue was deferred under this agreement, $5.0 million of which was included in current liabilities and $5.3 million of which was included in long-term liabilities. At December 31, 2012, $14.0 million of revenue was deferred under this agreement, $5.0 million of which was included in current liabilities and $9.0 million of which was included in long-term liabilities. *Pfizer, Inc.* In October 2010, the Company entered into a three year agreement with Pfizer to discover, develop and commercialize up to two DART-based molecules. The Company granted Pfizer a non-exclusive worldwide, royalty-bearing license and received an upfront payment of $5 million and has received milestone payments and funding for the Company’s internal and external research costs under the agreement. The Company is eligible to receive milestone payments of approximately $17 million related to pre-clinical and clinical development and $195 million related to commercialization and sales milestones for each DART program under this agreement. The Company has determined that each potential future technical and development milestone is substantive. Although sales milestones are not considered substantive, they are still recognized upon achievement of the milestone (assuming all other revenue recognition criteria have been met) because there are no undelivered elements that would preclude revenue recognition at that time. Pfizer is responsible for all pre-clinical and clinical development costs for the program. In addition, Pfizer is required to pay the Company mid-single digit to low-teen royalties on product sales. Under this collaboration, one DART program is currently being pursued and the Company will complete its research obligations under this program in January 2014. The Company has evaluated the research collaboration agreement with Pfizer and has determined that it is a revenue arrangement with multiple deliverables, or performance obligations. The Company’s substantive performance obligations under this research collaboration include an exclusive license to its technology, research and development services and manufacturing services. The Company concluded that the manufacturing services were optional and were subject to further negotiation upon reaching regulatory approval. As such, the manufacturing services are not included in the expected obligation period to perform services. The Company determined that it had fair value of the undelivered element of the research and development services. However, the Company concluded that the license does not have value on a standalone basis (e.g. absent the provision of the research and development services) and therefore does not represent a separate unit of accounting. Facts that were considered included the development of the candidate noting that because the drug candidate has not yet been developed, the license is of no value to Pfizer without the ensuing research and development activities using the DART technology, which is proprietary to the Company. Likewise, Pfizer could not sell the license to another party (without the Company agreeing to provide the research and development activities for the other party). Therefore, the upfront license fee and research and development services were treated as a combined unit of accounting and recognized over the expected obligation period associated with the research and development services through January 2014, which represents the estimated period of development. The $5 million upfront payment received by the Company is non-refundable; therefore, there is no right of return for the license. The Company is recognizing revenue associated with this non-refundable up-front license fee through January 2014. The Company and Pfizer have also agreed to establish a joint research committee to facilitate the governance and oversight of the parties’ activities under the agreements. Management considered whether participation on the joint committee may be a deliverable and determined that it was not a deliverable because it is a participating right and not an obligation of the Company. However, had management considered participation on the joint committee as a deliverable, it would not have had a material impact on the accounting for the arrangement. There have been no material modifications to this agreement since the adoption of ASU 2009-13 on January 1, 2011. Receivables of $501,794 and $896,285 as of September 30, 2013 and December 31, 2012, respectively, relate to amounts due to the Company from Pfizer for reimbursement work performed under the collaboration. The Company recognized revenues of approximately $0.9 million and $1.2 million under this agreement during the three months ended September 30, 2013 and 2012, respectively, and $3.2 million and $4.0 million during the nine months ended September 30, 2013 and 2012, respectively. Included in the 2012 revenues are milestone payments totaling $500,000. No additional milestones have been recognized under this agreement through September 30, 2013. At September 30, 2013 and December 31, 2012, $58,000 and $1.3 million of revenue was deferred under this agreement, all of which was included in current liabilities. *Green Cross Corporation* In June 2010, the Company entered into a collaboration agreement with Green Cross for the development of the Company’s anti-HER2 antibody known as MGAH22, or margetuximab. This arrangement grants Green Cross an exclusive license to conduct specified Phase 1 and Phase 2 clinical trials and commercialize margetuximab in South Korea. Upon execution of the agreement, Green Cross made a nonrefundable payment of $1.0 million to the Company. The Company is eligible to receive clinical development and commercial milestone payments of up to $4.5 million. The Company has determined that each potential clinical development and commercial milestone is substantive. The Company is also entitled to receive royalties on net sales of margetuximab in South Korea. The Company and Green Cross have formed a joint steering committee to coordinate and oversee activities on which the companies collaborate under the agreement. The Company has evaluated the collaboration agreement with Green Cross and has determined that it is a revenue arrangement with multiple deliverables or performance obligations. The Company’s substantive performance obligations under this agreement include an exclusive license to its technologies and participation in a joint steering committee. The Company concluded that the license does not have value on a standalone basis and therefore does not represent a separate unit of accounting. Likewise, Green Cross could not sell the license to another party. The $1 million upfront payment received by the Company is non-refundable; as such, there is no right of return for the license. Therefore, the upfront license fee and participation on the joint steering committee were treated as a combined unit of accounting and will be recognized over the term of the agreement through June 2020. There have been no material modifications to this agreement since the adoption of ASU 2009-13 on January 1, 2011. The Company recognized revenues of approximately $25,000 under this agreement during each of the three month periods ending September 30, 2013 and 2012, and $75,000 during each of the nine month periods ending September 30, 2013 and 2012. No milestones have been recognized under this agreement during the three and nine months ended September 30, 2013. At September 30, 2013, $675,000 of revenue was deferred under this agreement, $100,000 of which was included in current liabilities and $575,000 of which was included in long-term liabilities. At December 31, 2012, $750,000 of revenue was deferred under this agreement, $100,000 of which was included in current liabilities and $650,000 of which was included in long-term liabilities. *Eli Lilly & Co.* In October 2007, the Company entered into an exclusive license and collaboration agreement (together, the Agreements) with Eli Lilly to jointly develop and commercialize teplizumab, a humanized anti-CD3 monoclonal antibody. As part of the Agreements, Eli Lilly acquired the exclusive rights to the molecule. Upon execution of the Agreements, Eli Lilly made a nonrefundable payment of $41.0 million to the Company. In May 2008, Eli Lilly paid the Company a milestone payment of $50.0 million and in May 2010, Eli Lilly paid an additional milestone of $5.0 million. On October 28, 2010, Lilly notified the Company of its decision to terminate the agreement after review of one year of clinical data from the PROTÉGÉ trial in Type 1 diabetes patients treated with teplizumab. Such data failed to support the primary efficacy end point in the study. During the year ended December 31, 2012, Eli Lilly satisfied its obligation related to the cost of monitoring patients under the PROTÉGÉ and ENCORE trials. The Company’s obligations continued through September 2012, which represented the follow up period for enrolled patients and the Company’s final reporting of the trial’s results. There is no additional clinical trial activity under the Eli Lilly Agreements as it relates to such trials. In February 2011, the Company reacquired the commercial rights to the molecule from Eli Lilly. Receivables of $244,542 and $558,516 as of September 30, 2013 and December 31, 2012, respectively, relate to amounts due to the Company from Eli Lilly for reimbursement work performed under the above mentioned clinical trials. During the three months ended September 30, 2013 and 2012, the Company recognized revenue of $190,833 and $9.5 million, respectively, under this agreement. During the nine months ended September 30, 2013 and 2012, the Company recognized revenue of $673,927 and $30.1 million, respectively. No milestones were recognized under this agreement during the three and nine months ended September 30, 2013.

Commitments and Contingencies

9 Months Ended

Sep. 30, 2013

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

8. Commitments and Contingencies

Operating Leases

The Company leases office and laboratory space over periods extending through January 30, 2018. Several of the leases contain rent escalation clauses. Rent expense for the three months ended September 30, 2013 and 2012 was $806,275 and $783,462, respectively. The Company incurred $2.4 million of rent expense for each of the nine-month periods ending September 30, 2013 and 2012.

Future minimum lease payments under noncancelable operating leases at September 30, 2013 are as follows:


Twelve Months Ending September 30,
2014	$	3,460,609
2015		3,396,780
2016		3,385,321
2017		3,486,881
2018		3,035,013
Thereafter		625,540

	$	17,390,144

- Definition

The entire disclosure for commitments and contingencies.

+ References+ Details

Product Milestone Payments and Royalty Agreements	9 Months Ended
Product Milestone Payments and Royalty Agreements	Sep. 30, 2013
Text Block [Abstract]
Product Milestone Payments and Royalty Agreements	9. Product Milestone Payments and Royalty Agreements In connection with an Asset Purchase Agreement with Tolerance Therapeutics, Inc. (Tolerance) entered into during June 2005, the Company may be required to issue Tolerance additional consideration as follows: (i) $10,950,000 if certain milestones are met, including the initiation of Phase 3 trials and filing of various regulatory product license applications; (ii) 36,135 shares of common stock; and (iii) royalty payments between 1.75% and 4.0% of net sales of products acquired from or patented by Tolerance or other product fees earned by the Company. Any additional consideration required to be paid under the Asset Purchase Agreement will be recorded as research and development expense when incurred. No payments related to the additional consideration have occurred during the three and nine-month periods ended September 30, 2013 or 2012. Additionally, certain agreements require the Company to pay royalties. Currently, the Company is not obligated to pay royalties, as no other revenue from product sales is being generated by the Company.

Employee Benefit Plan	9 Months Ended
Employee Benefit Plan	Sep. 30, 2013
Compensation And Retirement Disclosure [Abstract]
Employee Benefit Plan	10. Employee Benefit Plan On September 25, 2002, the Company established the MacroGenics 401(k) Plan (the Plan) for its employees under Section 401(k) of the IRC. Under this Plan, all employees at least 21 years of age are eligible to participate in the Plan, starting on the first day of each month. Employees may contribute up to 100% of their salary, subject to government maximums. Employees are 100% vested in their contributions to the Plan. The Company’s contribution to the Plan, as determined by the Board of Directors, is discretionary. The Company’s contributions to the Plan totaled $55,311 and $48,891 for the three months ended September 30, 2013 and 2012, respectively, and $194,498 and $179,966 for the nine months ended September 30, 2013 and 2012, respectively.

Subsequent Events	9 Months Ended
Subsequent Events	Sep. 30, 2013
Subsequent Events [Abstract]
Subsequent Events	11. Subsequent Events On October 16, 2013, the Company completed its IPO, in which 5,000,000 shares of the Company’s common stock were sold at a price of $16 per share. Additionally, the underwriters of the Company’s IPO exercised the full amount of their over-allotment option resulting in the sale of an additional 750,000 shares of the Company’s common stock at a price of $16 per share. The Company received net proceeds of $83.8 million from the IPO, net of underwriting discounts and commissions and other estimated offering expenses. Upon consummation of the IPO, all outstanding shares of preferred stock automatically converted to common stock at the applicable conversion ratios then in effect. Subsequent to the IPO, the Company had 25,020,288 issued and outstanding shares of common stock and no outstanding shares of preferred stock. In November 2013, Boehringer nominated a bi-specific antibody therapeutic candidate generated by the Company’s DART technology for pre-clinical development. This formal selection of a development candidate triggered a $5.0 million milestone payment to the Company under the October 2010 agreement described in Note 7, Collaboration and License Agreements. In addition, Boehringer will pay a research maintenance payment of $4.0 million to the Company in the fourth quarter of 2013.

Summary of Significant Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2013

Accounting Policies [Abstract]

Use of Estimates

Use of Estimates

Cash and Cash Equivalents

Cash and Cash Equivalents

Accounts Receivable

Accounts Receivable

Deferred Intial Public Offering Costs

Deferred Initial Public Offering Costs

Restricted Cash

Restricted Cash

Fair Value of Financial Instruments

Fair Value of Financial Instruments

•

Level 1 – Fair value is determined by using unadjusted quoted prices that are available in active markets for identical assets and liabilities.

•

Financial assets and liabilities subject to fair value measurements were as follows:


	Fair Value Measurements at September 30, 2013
	Total			Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs
	Total			Level 1		Level 2		Level 3
Assets:
Cash and cash equivalents	$	7,522,029		$	7,522,029	$	—	$	—
Money market funds		26,047,169			26,047,169		—		—
Restricted cash		404,850			404,850		—		—

Total assets	$	33,974,048		$	33,974,048	$	—	$	—

Liabilities:
Preferred stock warrant liability	$	(679,296	)	$	—	$	—	$	(679,296	)


	Fair Value Measurements at December 31, 2012
	Total			Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs
	Total			Level 1		Level 2		Level 3
Assets:
Cash and cash equivalents	$	18,695,197		$	18,695,197	$	—	$	—
Money market funds		29,047,958			29,047,958		—		—
Restricted cash		404,850			404,850		—		—

Total assets	$	48,148,005		$	48,148,005	$	—	$	—

Liabilities:
Preferred stock warrant liability	$	(52,947	)	$	—	$	—	$	(52,947	)

As of December 31, 2012, the Company transferred its money market funds from Level 2 to Level 1 because the inputs are now based upon a quoted market price.


Balance at December 31, 2012	$	(52,947	)
Total unrealized gains (losses) included in earnings		(626,349	)

Balance at September 30, 2013	$	(679,296	)

Concentration of Credit Risk

Concentration of Credit Risk

The following table represents the percentage of all significant revenue earned in the periods indicated:


	Three Months Ended September 30,						Nine Months Ended September 30,
	2013			2012			2013			2012
Servier		71.3	%		14.2	%		58.8	%		12.6	%
Boehringer		11.5	%		15.6	%		15.9	%		17.2	%
Gilead		10.9	%		0.0	%		13.7	%		0.0	%
Pfizer		4.5	%		7.7	%		7.3	%		7.4	%
Government Agencies		0.6	%		3.5	%		2.6	%		6.9	%
Eli Lilly		0.9	%		59.0	%		1.6	%		55.7	%

The following table represents the percentage of all significant accounts receivable:


	September 30, 2013			December 31, 2012
Gilead		51.2	%		—
Pfizer		22.6	%		45.4	%
Boehringer		11.1	%		18.0	%
Eli Lilly		11.0	%		28.2	%
Government Agencies		4.0	%		8.4	%

Property and Equipment

Property and Equipment


Computer equipment		3 years
Software		3 years
Furniture		10 years
Laboratory and office equipment		5 years
Leasehold improvements		Shorter of lease term or useful life

Impairment of Long-Lived Assets

Impairment of Long-Lived Assets

Revenues

Revenues

Revenue Recognition

There are no performance, cancellation, termination or refund provisions in any of the arrangements that contain material financial consequences to the Company.

Exclusive Licenses

The Company does not directly control when any collaborator will achieve milestones or become liable for royalty payments.

Right-to-Develop Agreements

Research and Development Costs

Research and Development Costs

Comprehensive Income (Loss)

Comprehensive Income (Loss)

Stock-based Compensation

Stock-based Compensation

Net Income (Loss) Per Share

Net Income (Loss) Per Share

Basic and diluted income (loss) per common share is computed as follows:


	Three Months Ended September 30,						Nine Months Ended September 30,
	2013			2012			2013			2012
Net income (loss)	$	6,603,982		$	2,600,514		$	2,944,149		$	10,466,582
Less: undistributed earnings allocated to participating securities		(6,434,756	)		(2,600,514	)		(2,944,149	)		(10,466,582	)

Net income (loss) allocable to common shares	$	169,226		$	—		$	—		$	—

Basic weighted average common shares outstanding		1,184,507			1,092,307			1,463,798			1,078,145
Basic income (loss) per common share	$	0.14		$	—		$	—		$	—
Net income (loss)	$	6,603,982		$	2,600,514		$	2,944,149		$	10,466,582
Less: undistributed earnings allocated to participating securities and other add-backs to net income (loss)		(6,403,843	)		(2,600,514	)		(2,944,149	)		(10,466,582	)

Net income (loss) allocable to common shares	$	200,139		$	—		$	—		$	—

Basic weighted average common shares outstanding		1,184,507			1,092,307			1,463,798			1,078,145
Effect of dilutive securities		20,058,471			20,410,117			20,445,061			20,334,703

Diluted weighted average common shares outstanding		21,242,978			21,502,424			21,908,859			21,412,848

Diluted income (loss) per common share	$	0.01		$	—		$	—		$	—

The following common stock equivalents are included in the calculation of diluted net income (loss) per share:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2013		2012		2013		2012
Series A-1 Preferred Stock		2,156,114		2,156,114		2,156,114		2,156,114
Series A-2 Preferred Stock		392,274		392,274		392,274		392,274
Series B Preferred Stock		4,336,037		4,336,037		4,336,037		4,336,037
Series C Preferred Stock		5,909,906		5,909,906		5,909,906		5,909,906
Series D Preferred Stock		769,468		769,468		769,468		769,468
Series D-2 Preferred Stock		3,391,991		3,391,991		3,391,991		3,391,991
Warrants to purchase Series D-2 Preferred Stock		180,784		180,784		180,784		180,784
Stock Options		2,910,952		3,276,516		2,910,952		3,276,516

Recently Issued Accounting Standards Adopted

Recently Issued Accounting Standards Adopted

Summary of Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2013

Summary of Fair Value Measurement Financial Asset and Liabilities

Financial assets and liabilities subject to fair value measurements were as follows:


	Fair Value Measurements at September 30, 2013
	Total			Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs
	Total			Level 1		Level 2		Level 3
Assets:
Cash and cash equivalents	$	7,522,029		$	7,522,029	$	—	$	—
Money market funds		26,047,169			26,047,169		—		—
Restricted cash		404,850			404,850		—		—

Total assets	$	33,974,048		$	33,974,048	$	—	$	—

Liabilities:
Preferred stock warrant liability	$	(679,296	)	$	—	$	—	$	(679,296	)


	Fair Value Measurements at December 31, 2012
	Total			Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs
	Total			Level 1		Level 2		Level 3
Assets:
Cash and cash equivalents	$	18,695,197		$	18,695,197	$	—	$	—
Money market funds		29,047,958			29,047,958		—		—
Restricted cash		404,850			404,850		—		—

Total assets	$	48,148,005		$	48,148,005	$	—	$	—

Liabilities:
Preferred stock warrant liability	$	(52,947	)	$	—	$	—	$	(52,947	)

Summary of Preferred Stock Warrant Liability


Balance at December 31, 2012	$	(52,947	)
Total unrealized gains (losses) included in earnings		(626,349	)

Balance at September 30, 2013	$	(679,296	)

Estimated Useful Lives

Depreciation and amortization are computed using the straight-line method over the following estimated useful lives:


Computer equipment		3 years
Software		3 years
Furniture		10 years
Laboratory and office equipment		5 years
Leasehold improvements		Shorter of lease term or useful life

Schedule of Dilutive Securities Excluded from Computation of Diluted Net Income Per Share

Basic and diluted income (loss) per common share is computed as follows:


	Three Months Ended September 30,						Nine Months Ended September 30,
	2013			2012			2013			2012
Net income (loss)	$	6,603,982		$	2,600,514		$	2,944,149		$	10,466,582
Less: undistributed earnings allocated to participating securities		(6,434,756	)		(2,600,514	)		(2,944,149	)		(10,466,582	)

Net income (loss) allocable to common shares	$	169,226		$	—		$	—		$	—

Basic weighted average common shares outstanding		1,184,507			1,092,307			1,463,798			1,078,145
Basic income (loss) per common share	$	0.14		$	—		$	—		$	—
Net income (loss)	$	6,603,982		$	2,600,514		$	2,944,149		$	10,466,582
Less: undistributed earnings allocated to participating securities and other add-backs to net income (loss)		(6,403,843	)		(2,600,514	)		(2,944,149	)		(10,466,582	)

Net income (loss) allocable to common shares	$	200,139		$	—		$	—		$	—

Basic weighted average common shares outstanding		1,184,507			1,092,307			1,463,798			1,078,145
Effect of dilutive securities		20,058,471			20,410,117			20,445,061			20,334,703

Diluted weighted average common shares outstanding		21,242,978			21,502,424			21,908,859			21,412,848

Diluted income (loss) per common share	$	0.01		$	—		$	—		$	—

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share

The following common stock equivalents are included in the calculation of diluted net income (loss) per share:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2013		2012		2013		2012
Series A-1 Preferred Stock		2,156,114		2,156,114		2,156,114		2,156,114
Series A-2 Preferred Stock		392,274		392,274		392,274		392,274
Series B Preferred Stock		4,336,037		4,336,037		4,336,037		4,336,037
Series C Preferred Stock		5,909,906		5,909,906		5,909,906		5,909,906
Series D Preferred Stock		769,468		769,468		769,468		769,468
Series D-2 Preferred Stock		3,391,991		3,391,991		3,391,991		3,391,991
Warrants to purchase Series D-2 Preferred Stock		180,784		180,784		180,784		180,784
Stock Options		2,910,952		3,276,516		2,910,952		3,276,516

Summary of Significant Revenue [Member]

Summary of Percentage of Customer Concentration

The following table represents the percentage of all significant revenue earned in the periods indicated:


	Three Months Ended September 30,						Nine Months Ended September 30,
	2013			2012			2013			2012
Servier		71.3	%		14.2	%		58.8	%		12.6	%
Boehringer		11.5	%		15.6	%		15.9	%		17.2	%
Gilead		10.9	%		0.0	%		13.7	%		0.0	%
Pfizer		4.5	%		7.7	%		7.3	%		7.4	%
Government Agencies		0.6	%		3.5	%		2.6	%		6.9	%
Eli Lilly		0.9	%		59.0	%		1.6	%		55.7	%

Summary of Significant Accounts Receivable[Member]

Summary of Percentage of Customer Concentration

The following table represents the percentage of all significant accounts receivable:


	September 30, 2013			December 31, 2012
Gilead		51.2	%		—
Pfizer		22.6	%		45.4	%
Boehringer		11.1	%		18.0	%
Eli Lilly		11.0	%		28.2	%
Government Agencies		4.0	%		8.4	%

- Definition

Tabular disclosure of financial instruments measured at fair value, including those classified in shareholders' equity measured on a recurring or nonrecurring basis. Disclosures include, but are not limited to, fair value measurements recorded and the reasons for the measurements, level within the fair value hierarchy in which the fair value measurements are categorized and transfers between levels 1 and 2. Nonrecurring fair value measurements are those that are required or permitted in the statement of financial position in particular circumstances.

+ References+ Details

- Definition

Tabular disclosure of the fair value measurement of liabilities using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets), and gains or losses recognized in other comprehensive income (loss) and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issues, and settlements (each type disclosed separately); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs) by class of liability.

+ References+ Details

- Definition

Tabular disclosure of the nature of a concentration, a benchmark to which it is compared, and the percentage that the risk is to the benchmark.

+ References+ Details

Property and Equipment (Tables)

9 Months Ended

Sep. 30, 2013

Property Plant And Equipment [Abstract]

Schedule of Property and Equipment

Property and equipment consists of the following:


	September 30, 2013			December 31, 2012
Computer equipment	$	2,172,535		$	2,003,706
Software		1,323,081			1,323,081
Furniture		599,650			599,650
Lab equipment		10,603,598			8,747,790
Office equipment		51,360			51,360
Leasehold improvements		4,893,770			4,881,706

Property and equipment		19,643,994			17,607,293
Less accumulated depreciation and amortization		(15,174,112	)		(14,339,497	)

Property and equipment, net	$	4,469,882		$	3,267,796

Shared-Based Payments (Tables)

9 Months Ended

Sep. 30, 2013

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Schedule of Stock-Based Compensation Expense

The following stock-based compensation amounts were recognized for the periods indicated:


	Three Months Ended September 30				Nine Months Ended September 30
	2013		2012		2013		2012
Research and development	$	111,888	$	117,952	$	284,281	$	353,856
General and administrative		24,048		91,647		109,280		274,940

Total stock-based compensation expense	$	135,936	$	209,599	$	393,561	$	628,796

Schedule of Fair Value Option Award Estimated on the Date of Grant Using the Black-Scholes Option-Pricing Model

The fair value of each option award is estimated on the date of grant using the Black-Scholes option-pricing model using the assumptions in the following table:


	Nine Months Ended September 30,
	2013	2012
Expected dividend yield	0%	0%
Expected volatility	53% - 58%	51%
Risk-free interest rate	1.24% - 2.05%	1.18%
Expected average life of options	7 years	7 years
Fair market value of common stock at:	$1.50 - $7.51	$1.50
Expected forfeiture rate	5.06%	5.57%

Schedule of Stock Option Activity

The following table summarizes stock option activity under the Plan during the period then ended:


	Number of Options			Weighted- Average Exercise Price		Weighted- Average Contractual Term (in Years)
Outstanding, December 31, 2012		3,249,702			0.94		7.3
Granted		687,183			3.19		7.0
Exercised		(1,025,933	)		0.75
Forfeited or expired		(33,949	)		1.13

Outstanding, September 30, 2013		2,877,003			1.50		7.2

September 30, 2013:
Exercisable		1,855,178			0.94
Vested and Expected to Vest		918,600			2.44

Lease Exit Liability (Tables)

9 Months Ended

Sep. 30, 2013

Restructuring And Related Activities [Abstract]

Changes in Lease Exit Liability

Changes in the lease exit liability are as follows:


Accrual balance at December 31, 2011	$	10,607,499
Principal payments		(533,560	)

Accrual balance at December 31, 2012		10,073,939
Principal payments		(466,301	)

Accrual balance at September 30, 2013	$	9,607,638

Future Principal Payments Under Lease Agreement

Future principal payments to be made under the lease agreement for the next five years and thereafter as of September 30, 2013 are as follows:


Twelve Months Ending September 30,
2014	$	1,229,454
2015		1,589,410
2016		1,808,119
2017		2,049,273
2018		2,315,026
Thereafter		616,356

	$	9,607,638

Commitments and Contingencies (Tables)

9 Months Ended

Sep. 30, 2013

Commitments And Contingencies Disclosure [Abstract]

Schedule of Minimum Future Lease Payments Payables

Future minimum lease payments under noncancelable operating leases at September 30, 2013 are as follows:


Twelve Months Ending September 30,
2014	$	3,460,609
2015		3,396,780
2016		3,385,321
2017		3,486,881
2018		3,035,013
Thereafter		625,540

	$	17,390,144

- Definition

Tabular disclosure of a lessee's leasing arrangements including: (1) the basis on which contingent rental payments are determined, (2) the existence and terms of renewal or purchase options and escalation clauses, (3) restrictions imposed by lease arrangements, such as those concerning dividends, additional debt, and further leasing, (4) rent holidays, rent concessions, or leasehold improvement incentives and unusual provisions or conditions. Disclosure may also include the specific period used to amortize material leasehold improvements made at the inception of the lease or during the lease term. Additionally, for operating leases having initial or remaining noncancelable lease terms in excess of one year: (a) future minimum rental payments required as of the date of the latest balance sheet presented, in the aggregate and for each of the five succeeding fiscal years, (b) the total of minimum rentals to be received in the future under noncancelable subleases as of the date of the latest balance sheet presented, and (c) for all operating leases, rental expense for each period for which an income statement is presented, with separate amounts for minimum rentals, contingent rentals, and sublease rentals. Rental payments under leases with terms of a month or less that were not renewed need not be included.

+ References+ Details

Organization and Nature of Operations - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	9 Months Ended	1 Months Ended
	Sep. 30, 2013 Segment	Oct. 31, 2013 Subsequent Event [Member] IPO [Member]	Oct. 16, 2013 Subsequent Event [Member] IPO [Member]
Organization And Nature Of Business [Line Items]
MacroGenics incorporated date	Aug. 14, 2000
Number of operating segments	1
Initial public offering number of share sold		5,750,000
Initial public offering price per share			$ 16
Proceeds from initial public offering before offering expenses		$ 85.6

Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Accounting Policies [Abstract]
Allowance Recorded	$ 0	$ 0
Amounts classified as restricted cash	$ 404,850	$ 404,850

Summary of Significant Accounting Policies - Summary of Fair Value Measurement Financial Asset and Liabilities (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Assets:
Cash and cash equivalents	$ 7,522,029	$ 18,695,197
Money market funds	26,047,169	29,047,958
Restricted cash	404,850	404,850
Total assets	33,974,048	48,148,005
Liabilities:
Preferred stock warrant liability	(679,296)	(52,947)
Quoted Prices in Active Markets for Identical Assets Level 1 [Member]
Assets:
Cash and cash equivalents	7,522,029	18,695,197
Money market funds	26,047,169	29,047,958
Restricted cash	404,850	404,850
Total assets	33,974,048	48,148,005
Liabilities:
Preferred stock warrant liability
Significant Other Observable Inputs Level 2 [Member]
Assets:
Cash and cash equivalents
Money market funds
Restricted cash
Total assets
Liabilities:
Preferred stock warrant liability
Significant Unobservable Inputs Level 3 [Member]
Assets:
Cash and cash equivalents
Money market funds
Restricted cash
Total assets
Liabilities:
Preferred stock warrant liability	$ (679,296)	$ (52,947)

Summary of Significant Accounting Policies - Summary of Preferred Stock Warrant Liability (Detail) (Warrant [Member], USD $)	9 Months Ended
	Sep. 30, 2013
Warrant [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance beginning of year	$ (52,947)
Total unrealized gains (losses) included in earnings	(626,349)
Balance end of year	$ (679,296)

Summary of Significant Accounting Policies - Summary of Percentage of Significant Revenue (Detail) (Sales [Member])	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Servier [Member]
Concentration Risk [Line Items]
Percentage of all significant revenue earned	71.30%	14.20%	58.80%	12.60%
Boehringer [Member]
Concentration Risk [Line Items]
Percentage of all significant revenue earned	11.50%	15.60%	15.90%	17.20%
Gilead [Member]
Concentration Risk [Line Items]
Percentage of all significant revenue earned	10.90%	0.00%	13.70%	0.00%
Pfizer [Member]
Concentration Risk [Line Items]
Percentage of all significant revenue earned	4.50%	7.70%	7.30%	7.40%
Government Agencies [Member]
Concentration Risk [Line Items]
Percentage of all significant revenue earned	0.60%	3.50%	2.60%	6.90%
Eli Lilly [Member]
Concentration Risk [Line Items]
Percentage of all significant revenue earned	0.90%	59.00%	1.60%	55.70%

Summary of Significant Accounting Policies - Summary of Significant Accounts Receivable (Detail) (Accounts Receivable [Member])	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
Gilead [Member]
Concentration Risk [Line Items]
Significant Accounts Receivable	51.20%
Pfizer [Member]
Concentration Risk [Line Items]
Significant Accounts Receivable	22.60%	45.40%
Boehringer [Member]
Concentration Risk [Line Items]
Significant Accounts Receivable	11.10%	18.00%
Eli Lilly [Member]
Concentration Risk [Line Items]
Significant Accounts Receivable	11.00%	28.20%
Government Agencies [Member]
Concentration Risk [Line Items]
Significant Accounts Receivable	4.00%	8.40%

Summary of Significant Accounting Policies - Estimated Useful Lives (Detail)	9 Months Ended
	Sep. 30, 2013
Computer Equipment [Member]
Depreciation Amortization Impairment [Line Items]
Estimated Useful Lives	3 years
Software [Member]
Depreciation Amortization Impairment [Line Items]
Estimated Useful Lives	3 years
Furniture [Member]
Depreciation Amortization Impairment [Line Items]
Estimated Useful Lives	10 years
Laboratory and Office Equipment [Member]
Depreciation Amortization Impairment [Line Items]
Estimated Useful Lives	5 years
Leasehold Improvements [Member]
Depreciation Amortization Impairment [Line Items]
Leasehold improvements	Shorter of lease term or useful life

Summary of Significant Accounting Policies - Schedule of Dilutive Securities Excluded from Computation of Diluted Net Income Per Share (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Accounting Policies [Abstract]
Net income (loss)	$ 6,603,982	$ 2,600,514	$ 2,944,149	$ 10,466,582
Less: undistributed earnings allocated to participating securities	(6,434,756)	(2,600,514)	(2,944,149)	(10,466,582)
Net income (loss) allocable to common shares	169,226
Basic weighted average common shares outstanding	1,184,507	1,092,307	1,463,798	1,078,145
Basic income (loss) per common share	$ 0.14	$ 0.00	$ 0.00	$ 0.00
Net income (loss)	6,603,982	2,600,514	2,944,149	10,466,582
Less: undistributed earnings allocated to participating securities and other add-backs to net income (loss)	(6,403,843)	(2,600,514)	(2,944,149)	(10,466,582)
Net income (loss) allocable to common shares	$ 200,139
Basic weighted average common shares outstanding	1,184,507	1,092,307	1,463,798	1,078,145
Effect of dilutive securities	20,058,471	20,410,117	20,445,061	20,334,703
Diluted weighted average common shares outstanding	21,242,978	21,502,424	21,908,859	21,412,848
Diluted income per common share	$ 0.01	$ 0.00	$ 0.00	$ 0.00

Summary of Significant Accounting Policies - Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Series A-1 Convertible Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Preferred Stock	2,156,114	2,156,114	2,156,114	2,156,114
Series A-2 Convertible Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Preferred Stock	392,274	392,274	392,274	392,274
Series B Convertible Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Preferred Stock	4,336,037	4,336,037	4,336,037	4,336,037
Series C Convertible Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Preferred Stock	5,909,906	5,909,906	5,909,906	5,909,906
Series D Convertible Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Preferred Stock	769,468	769,468	769,468	769,468
Series D-2 Convertible Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Preferred Stock	3,391,991	3,391,991	3,391,991	3,391,991
Warrant [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Preferred Stock	180,784	180,784	180,784	180,784
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Preferred Stock	2,910,952	3,276,516	2,910,952	3,276,516

- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References+ Details

Property and Equipment - Schedule of Property and Equipment (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Property and equipment	$ 19,643,994	$ 17,607,293
Less accumulated depreciation and amortization	(15,174,112)	(14,339,497)
Property and equipment, net	4,469,882	3,267,796
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	2,172,535	2,003,706
Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	1,323,081	1,323,081
Furniture [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	599,650	599,650
Lab Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	10,603,598	8,747,790
Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	51,360	51,360
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	$ 4,893,770	$ 4,881,706

Stockholders' Equity (Deficit) - Additional Information (Detail) (USD $)	9 Months Ended			24 Months Ended		9 Months Ended	1 Months Ended					9 Months Ended			1 Months Ended	9 Months Ended	1 Months Ended	9 Months Ended
	Sep. 30, 2013	May 31, 2006	Oct. 31, 2004	Dec. 31, 2003 Series A Preferred Stock [Member]	Sep. 30, 2013 Series A Preferred Stock [Member]	Sep. 30, 2013 Series D Preferred Stock [Member]	Mar. 31, 2011 Series D Preferred Stock [Member] Raven Biotechnologies Inc [Member]	Jul. 31, 2008 Series D Preferred Stock [Member] Raven Biotechnologies Inc [Member]	Jan. 31, 2011 Series D Two Preferred Stock [Member]	May 30, 2010 Series D Two Preferred Stock [Member]	Sep. 30, 2008 Series D Two Preferred Stock [Member]	Sep. 30, 2013 Series D Two Preferred Stock [Member]	Sep. 30, 2013 Series A- One Preferred Stock [Member]	Sep. 30, 2013 Series A- Two Preferred Stock [Member]	Oct. 31, 2004 Series B Preferred Stock [Member]	Sep. 30, 2013 Series B Preferred Stock [Member]	May 31, 2006 Series C Preferred Stock [Member]	Sep. 30, 2013 Series C Preferred Stock [Member]
Stockholders Equity [Line Items]
Number of shares issued or sold				34,239,374					18,427,388	6,916,110	38,337,678				71,401,237		110,952,217
Proceeds from issuance of convertible preferred stock				$ 34,000,000					$ 12,016,500		$ 24,843,211				$ 30,261,672		$ 44,898,754
Convertible Preferred Stock Per Share				$ 1.00
Related offering costs											156,788				238,000		101,246
Shares of common stock allocated but unissued		10,003,300	13,604,016
Shares issued to acquire entity							14,446,227	12,466,039
Purchased shares										518,708	2,875,327
Exercise price												0.65
Outstanding stock	4,000,000
Percentage of preferred stock holders with voting rights of board members	66.67%
Accrued noncumulative dividends on preferred stock						$ 0.0522						$ 0.0522	$ 0.08	$ 0.08		$ 0.0341		$ 0.0324
Convertible preferred stock series						1.00						1.00	1.506	1.00		1.14		1.00
Conversion price of preferred stock						$ 12.20						$ 12.20	$ 12.39	$ 18.77		$ 6.95		$ 7.70
Reserved common stock	17,129,782
Net proceeds from underwritten public offering upon closing of firm	$ 40,000,000
Earning per share received by the shareholders					$ 12.39	$ 12.20						$ 12.20				$ 6.95		$ 7.70
Reverse stock split	1-for-18.7739

Shared-Based Payments - Additional Information (Detail) (USD $)	9 Months Ended		12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Dec. 31, 2010	Dec. 31, 2008	Dec. 31, 2006	Dec. 31, 2003
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Aggregate of shares							2,051,644
Increase in aggregate of shares			4,336,731	3,790,760	3,258,106	2,512,390
Common Stock			545,970	532,654	745,716	460,746
Shares available for issuance	8,171
Expected life of option term	7 years	7 years
Aggregate intrinsic value of options outstanding	$ 17,400,000
Aggregate intrinsic value of options exercisable	12,200,000
Equity Incentive Plan 2003 [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Expected life of option term	7 years
Weighted-average grant-date fair value of options granted	$ 2.00
Total cash received for the options exercised	851,183
Fair value of shares vested	402,084
Unrecognized compensation expense recognition period	4 years
Equity Incentive Plan 2003 [Member] \| Equity Incentive Plan Two Thousand [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Unrecognized compensation cost related to non-vested stock-based compensation arrangements	$ 1,500,000
Equity Incentive Plan 2003 [Member] \| Maximum [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Options granted, maximum term	10 years
Stock Option Plan 2000 [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Aggregate of shares	130,725
Increase in aggregate of shares	150,297

Shared-Based Payments - Schedule of Stock-Based Compensation Expense (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 135,936	$ 209,599	$ 393,561	$ 628,796
Research and Development Expense [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	111,888	117,952	284,281	353,856
General and Administrative Expense [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 24,048	$ 91,647	$ 109,280	$ 274,940

Shared-Based Payments - Schedule of Fair Value Option Award Estimated on the Date of Grant Using the Black-Scholes Option-Pricing Model (Detail) (USD $)	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield	0.00%	0.00%
Expected volatility		51.00%
Risk-free interest rate		1.18%
Expected average life of options	7 years	7 years
Fair market value of common stock at:		$ 1.50
Expected forfeiture rate	5.06%	5.57%
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	53.00%
Risk-free interest rate	1.24%
Fair market value of common stock at:	$ 1.50
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	58.00%
Risk-free interest rate	2.05%
Fair market value of common stock at:	$ 7.51

Shared-Based Payments - Schedule of Stock Option Activity (Detail) (USD $)	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Options, Outstanding, Beginning Balance	3,249,702
Number of Options, Granted	687,183
Number of Options, Exercised	(1,025,933)
Number of Options, Forfeited or expired	(33,949)
Number of Options, Outstanding, Ending Balance	2,877,003	3,249,702
Number of Options, Exercisable	1,855,178
Number of Options, Vested and expected to vest	918,600
Weighted- Average Exercise Price, Outstanding, Beginning Balance	$ 0.94
Weighted- Average Exercise Price, Granted	$ 3.19
Weighted- Average Exercise Price, Exercised	$ 0.75
Weighted- Average Exercise Price, Forfeited or expired	$ 1.13
Weighted- Average Exercise Price, Outstanding, Ending Balance	$ 1.50	$ 0.94
Weighted- Average Exercise Price, Exercisable	$ 0.94
Weighted- Average Exercise Price, Vested and expected to vest	$ 2.44
Weighted Average Contractual Term, Granted	7 years
Weighted Average Contractual Term, Outstanding	7 years 3 months 12 days	7 years 3 months 18 days

Lease Exit Liability - Additional Information (Detail) (USD $)	1 Months Ended	9 Months Ended
	Jul. 16, 2008	Sep. 30, 2013	Sep. 30, 2012
Restructuring Cost and Reserve [Line Items]
Operating Lease	2018
Onetime purchase payment under purchase agreement	$ 5,000,000
Additional amounts recorded		0	0
Minimum [Member]
Restructuring Cost and Reserve [Line Items]
Onetime payment paid under license of product	8,000,000
Maximum [Member]
Restructuring Cost and Reserve [Line Items]
Onetime payment paid under license of product	$ 12,000,000
Convertible Preferred Stock Series D [Member]
Restructuring Cost and Reserve [Line Items]
Shares issued in connection with acquisition	12,466,039

Lease Exit Liability - Changes in Lease Exit Liability (Detail) (Contract Termination [Member], USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Sep. 30, 2013
Contract Termination [Member]
Restructuring Cost and Reserve [Line Items]
Accrual balance	$ 10,073,939	$ 10,607,499	$ 9,607,638
Principal payments	$ (466,301)	$ (533,560)

Lease Exit Liability - Future Principal Payments under Lease Agreement (Detail) (USD $)	Sep. 30, 2013
Clone 1 Of Future Minimum Leases Payments Under Leases (Line Items)
2014	$ 3,460,609
2015	3,396,780
2016	3,385,321
2017	3,486,881
2018	3,035,013
Thereafter	625,540
Total	17,390,144
Contract Termination [Member]
Clone 1 Of Future Minimum Leases Payments Under Leases (Line Items)
2014	1,229,454
2015	1,589,410
2016	1,808,119
2017	2,049,273
2018	2,315,026
Thereafter	616,356
Total	$ 9,607,638

Collaboration and License Agreements - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended			3 Months Ended		9 Months Ended			3 Months Ended		9 Months Ended			3 Months Ended	9 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended	1 Months Ended		3 Months Ended		9 Months Ended		12 Months Ended	3 Months Ended		9 Months Ended			1 Months Ended		3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Sep. 30, 2013 Les Laboratoires Servier [Member]	Sep. 30, 2012 Les Laboratoires Servier [Member]	Sep. 30, 2013 Les Laboratoires Servier [Member]	Sep. 30, 2012 Les Laboratoires Servier [Member]	Dec. 31, 2012 Les Laboratoires Servier [Member]	Sep. 30, 2013 Les Laboratoires Servier [Member] Second Right to Develop Collaboration [Member]	Sep. 30, 2012 Les Laboratoires Servier [Member] Second Right to Develop Collaboration [Member]	Sep. 30, 2013 Les Laboratoires Servier [Member] Second Right to Develop Collaboration [Member]	Sep. 30, 2012 Les Laboratoires Servier [Member] Second Right to Develop Collaboration [Member]	Dec. 31, 2012 Les Laboratoires Servier [Member] Second Right to Develop Collaboration [Member]	Sep. 30, 2013 Gilead [Member]	Sep. 30, 2013 Gilead [Member] Molecule Program	Sep. 30, 2013 Boehringer [Member]	Sep. 30, 2012 Boehringer [Member]	Sep. 30, 2013 Boehringer [Member] Molecule Payments	Sep. 30, 2012 Boehringer [Member]	Dec. 31, 2012 Boehringer [Member]	Jan. 31, 2011 Boehringer [Member] Series D-2 Convertible Preferred Stock [Member]	Oct. 31, 2010 Pfizer [Member] Molecule	Sep. 30, 2013 Pfizer [Member]	Sep. 30, 2012 Pfizer [Member]	Sep. 30, 2013 Pfizer [Member] Program	Sep. 30, 2012 Pfizer [Member]	Dec. 31, 2012 Pfizer [Member]	Sep. 30, 2013 Green Cross Corporation [Member]	Sep. 30, 2012 Green Cross Corporation [Member]	Sep. 30, 2013 Green Cross Corporation [Member]	Sep. 30, 2012 Green Cross Corporation [Member]	Dec. 31, 2012 Green Cross Corporation [Member]	Oct. 28, 2010 Eli Lilly [Member]	May 31, 2008 Eli Lilly [Member]	Sep. 30, 2013 Eli Lilly [Member]	Sep. 30, 2012 Eli Lilly [Member]	Sep. 30, 2013 Eli Lilly [Member]	Sep. 30, 2012 Eli Lilly [Member]	Dec. 31, 2012 Eli Lilly [Member]
License And Collaboration Agreements [Line Items]
Collaboration agreement date								November 2011					September 2012				January 2013			October 2010				October 2010								June 2010							October 2007
Non-refundable upfront payment								$ 20,000,000					$ 20,000,000							$ 15,000,000				$ 5,000,000			$ 5,000,000					$ 1,000,000							$ 41,000,000
License grant fees						30,000,000		30,000,000			65,000,000		65,000,000			7,500,000	7,500,000
Clinical milestone payments								47,000,000					98,000,000
Regulatory milestone payments						140,000,000		140,000,000			300,000,000		300,000,000			355,000,000	355,000,000	89,000,000		89,000,000
Sales milestone payments								208,000,000					630,000,000				500,000,000			83,000,000							195,000,000
Expected period of development								27 months					29 months				21 months
Recognized revenue under agreement	20,111,173	15,532,680	42,015,994	50,283,510		12,300,000	2,300,000	18,900,000	6,800,000		2,200,000	0	6,500,000	0		2,200,000	5,900,000	2,300,000	2,500,000	6,900,000	9,300,000				900,000	1,200,000	3,200,000	4,000,000		25,000	25,000	75,000	75,000				190,833.0	9,500,000	673,927.0	30,100,000
Milestone payment						10,000,000		10,000,000												41,000,000		2,000,000							500,000							50,000,000
Deferred revenue						3,100,000		3,100,000		10,000,000	11,600,000		11,600,000		18,000,000			10,300,000		10,300,000		14,000,000								675,000		675,000		750,000
Deferred revenue included in current liabilities	21,298,318		21,298,318		24,123,176					9,100,000	8,600,000		8,600,000		8,600,000	4,400,000	4,400,000	5,000,000		5,000,000		5,000,000			58,000,000,000		58,000,000,000		1,300,000	100,000		100,000		100,000
Deferred revenue included in long-term liabilities	8,812,342		8,812,342		19,956,343					900,000	3,000,000		3,000,000		9,400,000			5,300,000		5,300,000		9,000,000								575,000		575,000		650,000
Clinical milestone payments under agreement											5,000,000		5,000,000			200,000,000	200,000,000								17,000,000		17,000,000			4,500,000		4,500,000
Commercialization of molecules																	4			10				2
Molecules having exclusive worldwide rights																	3
Number of programs Company retains development and commercialization rights outside																	1
Additional license grant fees																22,500,000	22,500,000
Receivables	2,281,282		2,281,282		2,046,219											1,100,000	1,100,000	246,375		246,375		355,568			501,794		501,794		896,285								244,542		244,542		558,516
Number of annual maintenance payments received																				2
Received including upfront, annual maintenance and milestone payment																				39,000,000
Preferred Stock purchased																							$ 10,000,000
Research obligation completion date																				2015-09							2014-01
Period of agreement																								3 years
DART program																											1
Term of the agreement																																2020-06
Review of clinical data																																			1 year

Commitments and Contingencies - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Commitments And Contingencies Disclosure [Abstract]
Rent expense	$ 806,275	$ 783,462	$ 2,400,000	$ 2,400,000
Lease expiration date			Jan. 30, 2018

Commitments and Contingencies - Schedule of Minimum Future Lease Payments Receivable (Detail) (USD $)	Sep. 30, 2013
Commitments And Contingencies Disclosure [Abstract]
2014	$ 3,460,609
2015	3,396,780
2016	3,385,321
2017	3,486,881
2018	3,035,013
Thereafter	625,540
Total	$ 17,390,144

Product Milestone Payments and Royalty Agreements - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended		9 Months Ended
	Jun. 30, 2005	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Royalty Agreement [Line Items]
Additional consideration of asset purchase agreement	$ 10,950,000
Common stock shares	36,135
Payments related to the additional considerations		$ 0	$ 0	$ 0	$ 0
Minimum [Member]
Royalty Agreement [Line Items]
Maximum royalty payments percentage	1.75%
Maximum [Member]
Royalty Agreement [Line Items]
Maximum royalty payments percentage	4.00%

Employee Benefit Plan - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended		9 Months Ended
	Sep. 30, 2002 Age	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Defined Contribution Pension And Other Postretirement Plans Disclosure [Abstract]
Eligibility of employee participation plan	21
Percentage of employee contribution to salary	100.00%
Percentage of employee vested contribution				100.00%
Company's contribution to plan total		$ 55,311	$ 48,891	$ 194,498	$ 179,966

Subsequent Events - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified				1 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Oct. 16, 2013 Subsequent Event [Member]	Oct. 31, 2013 Subsequent Event [Member] IPO [Member]	Oct. 16, 2013 Subsequent Event [Member] IPO [Member]
Subsequent Event [Line Items]
Initial public offering number of share sold				5,000,000
Initial public offering price per share					$ 16
Additional shares sold under over-allotments Option to underwriter				750,000
Proceeds from initial public offering net of expenses				$ 83.8
Common stock, shares issued	2,124,624	1,098,914	25,020,288
Common stock, shares outstanding	2,124,624	1,098,914	25,020,288
Preferred stock, shares outstanding			0
Milestone Payments Triggered	5.0
Research Maintenance Payment Receivable	$ 4.0