Selected Quarterly Financial Data

12 Months Ended

Dec. 31, 2013

Quarterly Financial Information Disclosure [Abstract]

Selected Quarterly Financial Data

19. Selected Quarterly Financial Data (Unaudited)

The following table contains quarterly financial information for 2013 and 2012. The Company believes that the following information reflects all normal recurring adjustments necessary for a fair statement of the information for the periods presented. The operating results for any quarter are not necessarily indicative of results for any future period.

	First Quarter			Second Quarter			Third Quarter			Fourth Quarter
	(in thousands, except per share data)
2013
Collaboration revenues	$	14,655		$	18,452		$	6,856		$	7,823
Total operating expenses		41,921			47,560			42,780			36,065
Net loss		(28,323	)		(30,251	)		(39,763	)		(32,348	)
Net loss attributable to Merrimack Pharmaceuticals, Inc.		(28,153	)		(30,082	)		(39,631	)		(33,059	)
Net loss per share available to common stockholders—basic and diluted	$	(0.29	)	$	(0.31	)	$	(0.39	)	$	(0.33	)

	First Quarter			Second Quarter			Third Quarter			Fourth Quarter
	(in thousands, except per share data)
2012
Collaboration revenues	$	11,344		$	12,063		$	11,323		$	14,191
Total operating expenses		35,379			32,368			35,197			38,719
Net loss		(23,402	)		(20,139	)		(23,320	)		(24,893	)
Net loss attributable to Merrimack Pharmaceuticals, Inc.		(23,284	)		(20,026	)		(23,199	)		(24,768	)
Net loss per share available to common stockholders—basic and diluted	$	(2.14	)	$	(0.22	)	$	(0.25	)	$	(0.26	)