Stock-based compensation (Tables)

6 Months Ended

9 Months Ended

Jun. 30, 2012

Dec. 31, 2011

Stock-based compensation

Summary of the Company's stock option activity and related information

	Shares			Weighted average price per share		Weighted average remaining contractual term (years)		Aggregate intrinsic value
Outstanding at December 31, 2011		617,633			0.04		9.8	$	2,162
Granted		167,275			4.30
Forfeited		(98,366	)		0.29
Outstanding at June 30, 2012		686,542			1.04		9.41	$	2,991
Exercisable at June 30, 2012		22,057			0.84		9.36	$	101
Vested and expected to vest at June 30, 2012		686,542			1.04		9.41	$	2,991

	Shares		Weighted average price per share		Weighted average remaining contractual term (years)		Aggregate intrinsic value
Outstanding at April 5, 2011(inception)		—		—
Granted		617,633		0.04
Outstanding at December 31, 2011		617,633		0.04		9.8	$	2,162
Exercisable at December 31, 2011		—		—		—		—
Vested and expected to vest at December 31, 2011		617,633		0.04		9.8	$	2,162

Summary of the Company's restricted stock activity and related information

	Shares			Weighted-average purchase price per share
Outstanding at December 31, 2011		2,319,646		$	0.002
Granted		—
Vested		(345,480	)	$	0.002
Outstanding at June 30, 2012		1,974,166		$	0.002

	Shares		Weighted average purchase price per share
Outstanding at April 5, 2011(inception)		—	$	—
Granted		3,529,406	$	0.002
Vested		1,209,760	$	0.002
Outstanding at December 31, 2011		2,319,646	$	0.002

Schedule of assumptions used to estimate fair value of each stock-based award on the grant date using the Black-Scholes option pricing model

	Three Months Ended June 30, 2012			Six Months Ended June 30, 2012
	(Unaudited)			(Unaudited)
Risk-free interest rate		0.8 - 1.2	%		0.8 - 1.2	%
Dividend yield		—			—
Volatility		84 - 87	%		84 - 87	%
Expected term (years)		5.1 - 6.1			5.1 - 6.1

	December 31, 2011
Risk-free interest rate		1.2	%
Dividend yield		—
Volatility		79	%
Expected term (years)		6.0