| Summary of financial assets and liabilities measured at fair value on a recurring basis |
The following tables summarize the financial assets and liabilities measured at fair value on a recurring basis in the accompanying balance sheets as of December 31, 2014 and 2013 (in thousands):
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As of December 31, 2014
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Level 1
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Level 2
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Level 3
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Total
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Assets
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Cash and cash equivalents:
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Cash
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$
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1,519
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$
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—
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$
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—
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$
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1,519
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Money market funds(1)
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23,994
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—
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—
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23,994
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Domestic corporate debt securities(2)
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—
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3,005
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—
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3,005
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Total
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$
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25,513
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$
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3,005
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$
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—
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$
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28,518
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Marketable securities:
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Domestic corporate debt securities(2)
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$
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—
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$
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69,509
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$
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—
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$
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69,509
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Domestic corporate commercial paper(2)
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—
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7,249
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—
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7,249
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Total
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$
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—
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$
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76,758
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$
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—
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$
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76,758
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As of December 31, 2013
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Level 1
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Level 2
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Level 3
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Total
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Assets
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Cash and cash equivalents:
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Cash
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$
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2,710
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$
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—
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$
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—
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$
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2,710
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Money market funds(1)
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9,593
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—
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—
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9,593
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$
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12,303
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$
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—
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$
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—
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$
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12,303
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Liabilities
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Warrant liability(3)
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$
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—
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$
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—
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$
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1,945
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$
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1,945
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Stock Liability(3)
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—
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—
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5,328
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5,328
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$
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—
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$
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—
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$
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7,273
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$
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7,273
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(1)
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Fair value is based upon quoted market prices.
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(2)
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Fair value is based upon quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active and model-based valuation techniques for which all significant assumptions are observable in the market or can be corroborated by observable market data for substantially the full term of the assets. Inputs are obtained from various sources, including market participants, dealers and brokers.
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(3)
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Fair value is determined using the probability-weighted expected return model ("PWERM"), as discussed below. Changes in the fair value of the Level 3 assets and liabilities are recorded as other (expense) income in the statement of operations.
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| Roll-forward of fair value of assets determined by Level 3 inputs |
The following table provides a roll forward of the fair value of the assets, where fair value is determined using Level 3 inputs (in thousands):
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Balance at December 31, 2013
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$
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—
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Issuance of shares of Series A-6—prepayment
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1,220
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Nordic amendment
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(1,220
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)
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Balance at December 31, 2014
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$
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—
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| Roll-forward of fair value of liabilities determined by Level 3 inputs |
The following table provides a roll forward of the fair value of the liabilities, where fair value is determined using Level 3 inputs (in thousands):
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Balance at December 31, 2013
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$
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7,273
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Issuance of shares of Series A-6
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(8,889
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)
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Additions—accrued shares of Series A-6
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2,717
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Additions—warrants
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1,511
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Change in fair value
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|
505
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Warrant liability reclassified to equity
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(3,117
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)
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Balance at December 31, 2014
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$
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—
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