Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Cash flows from operating activities:
Net loss	$ (72,415)	$ (6,647)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	7,649	8,334
Stock-based compensation	9,682	8,105
Other non-cash transactions	620	(205)
Changes in operating assets and liabilities:
Accounts receivable	16,642	(4,645)
Inventory	(2,531)	(3,306)
Other assets	(2,191)	(136)
Accounts payable	(3,149)	2,183
Accrued compensation	183	(2,144)
Accrued expenses	2,371	1,012
Accrued clinical trial expenses	1,688	(818)
Deferred revenue	(7,549)	(55,120)
Other liabilities	(658)	(729)
Net cash used in operating activities	(49,658)	(54,116)
Cash flows from investing activities:
Purchases of investments	(509,681)	(218,275)
Sales of investments	180,478	8,197
Maturities of investments	156,962	241,256
Purchases of property and equipment	(6,845)	(8,796)
Net cash (used in) provided by investing activities	(179,086)	22,382
Cash flows from financing activities:
Payments of loan and capital lease obligations	(934)	(731)
Issuance of common stock, net of issuance costs	223,549	6,148
Net cash provided by financing activities	222,615	5,417
Effect of exchange rates on cash and cash equivalents	0	(36)
Net decrease in cash and cash equivalents	(6,129)	(26,353)
Cash and cash equivalents at beginning of period	17,755	49,597
Cash and cash equivalents at end of period	$ 11,626	$ 23,244

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The portion of consolidated profit or loss for the period, net of income taxes, which is attributable to the parent. If the entity does not present consolidated financial statements, the amount of profit or loss for the period, net of income taxes.

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The cash inflow associated maturities (principal being due), prepayments and calls (requests of early payments) on securities not classified as either held-to-maturity securities or trading securities which are classified as available-for-sale securities.

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