Income Taxes (Tables)

12 Months Ended

Dec. 31, 2012

Significant Components of Deferred Tax Assets

Significant components of the Company’s deferred tax assets are as follows (in thousands):

	December 31,
	2012			2011
Deferred Tax Assets:
Net operating Losses	$	37,162		$	26,699
Research & Other Credits		2,008			2,029
Deferred Revenue		—			1,559
Other		1,030			750
Total Deferred Tax Assets		40,200			31,037
Valuation Allowance		(40,200	)		(31,037	)
Net Deferred Tax Assets	$	—		$	—

Reconciliation of Statutory Tax Rates And Effective Tax Rates

A reconciliation of the statutory tax rates and the effective tax rates for the years ended December 2012, 2011, and 2010 is as follows:

	Years Ended December 31,
	2012			2011			2010
Statutory rate		-34.0	%		-34.0	%		-34.0	%
Valuation Allowance		33.4	%		31.0	%		40.8	%
Nondeductible Warrant Expense		-0.1	%		0.0	%		0.0	%
Nondeductible Stock Compensation		0.6	%		2.6	%		3.2	%
R&D expense adjustment related to Grants received		0.0	%		0.0	%		-10.4	%
Other		0.1	%		0.4	%		0.4	%
Effective tax rate		0.0	%		0.0	%		0.00	%

Reconciliation of Beginning And Ending Amount Of Unrecognized Tax Benefits

A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (in thousands):

Beginning at January 1, 2010	$	850
Additions based on tax positions related to current year		172
Balance at December 31, 2010		1,022
Additions based on tax positions related to current year		3
Balance at December 31, 2011		1,025
Additions based on tax positions related to prior year		39
Additions based on tax positions related to current year		5
Balance at December 31, 2012	$	1,069