4. INVESTMENTS

Investments consist of the following:

			Gross Unrealized

					Losses
(In thousands)	Amortized Cost		Gains		Less than One Year			Greater than One Year			Estimated Fair Value
March 31, 2013
Short-term investments:
Available-for-sale securities:
U.S. government and agency debt securities	$	102,093	$	29	$	(1	)	$	—		$	102,121
Corporate debt securities		10,946		27		—			—			10,973
International government agency debt securities		10,089		8		(1	)		—			10,096

		123,128		64		(2	)		—			123,190

Money market funds		1,201		—		—			—			1,201

		124,329		64		(2	)		—			124,391

Long-term investments:
Available-for-sale securities:
U.S. government and agency debt securities		60,047		—		(17	)		—			60,030
Corporate debt securities		18,725		—		(26	)		(162	)		18,537
International government agency debt securities		3,060		—		—			—			3,060

		81,832		—		(43	)		(162	)		81,627

Held-to-maturity securities:
Certificates of deposit		1,200		—		—			—			1,200

		83,032		—		(43	)		(162	)		82,827

Total investments	$	207,361	$	64	$	(45	)	$	(162	)	$	207,218

March 31, 2012
Short-term investments:
Available-for-sale securities:
U.S. government and agency debt securities	$	62,925	$	67	$	(17	)	$	—		$	62,975
International government agency debt securities		25,646		22		(2	)		—			25,666
Corporate debt securities		12,324		27		—			—			12,351

		100,895		116		(19	)		—			100,992

Held-to-maturity securities:
Certificates of deposit		4,236		—		—			—			4,236
U.S. government obligations		417		—		—			—			417

		4,653		—		—			—			4,653

Money market funds		1,201		—		—			—			1,201

		106,749		116		(19	)		—			106,846

Long-term investments:
Available-for-sale securities:
U.S. government and agency debt securities		35,493		—		(70	)		—			35,423
International government agency debt securities		10,257		—		(20	)		—			10,237
Corporate debt securities		8,009		—		—			(660	)		7,349
Strategic investments		644		838		—			—			1,482

		54,403		838		(90	)		(660	)		54,491

Held-to-maturity securities:
Certificates of deposit		1,200		—		—			—			1,200

		55,603		838		(90	)		(660	)		55,691

Total investments	$	162,352	$	954	$	(109	)	$	(660	)	$	162,537

The proceeds from the sales and maturities of marketable securities, excluding strategic equity investments, which were primarily reinvested and resulted in realized gains and losses, were as follows:

	Year Ended March 31,

(In thousands)	2013		2012		2011
Proceeds from the sales and maturities of marketable securities	$	258,937	$	323,028	$	385,511
Realized gains	$	39	$	47	$	77
Realized losses	$	5	$	11	$	32

In addition, during the year ended March 31, 2013, the Company sold $4.7 million of its held-to-maturity securities. These securities were held as collateral for certain lease agreements that ended in June 2012. There were no gains or losses recognized on the sale of these investments. The Company's available-for-sale and held-to-maturity securities at March 31, 2013 have contractual maturities in the following periods:

	Available-for-sale				Held-to-maturity

(In thousands)	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
Within 1 year	$	80,388	$	80,399	$	1,200	$	1,200
After 1 year through 5 years		124,572		124,418		—		—

Total	$	204,960	$	204,817	$	1,200	$	1,200

At March 31, 2013, the Company believes that the unrealized losses on its available-for-sale investments are temporary. The investments with unrealized losses consist primarily of corporate debt securities. In making the determination that the decline in fair value of these securities was temporary, the Company considered various factors, including but not limited to: the length of time each security was in an unrealized loss position; the extent to which fair value was less than cost; financial condition and near-term prospects of the issuers; and the Company's intent not to sell these securities, and the assessment that it is more likely than not that the Company would not be required to sell these securities before the recovery of their amortized cost basis.

The Company's investment in Acceleron Pharma, Inc. ("Acceleron") was $8.7 million at March 31, 2013 and 2012, which is recorded within "Other assets" in the accompanying consolidated balance sheets. The Company accounts for its investment in Acceleron under the cost method as Acceleron is a privately-held company over which the Company does not exercise significant influence. The Company continues to monitor this investment to evaluate whether any decline in its value has occurred that would be other-than-temporary, based on the implied value from any recent rounds of financing completed by Acceleron, market prices of comparable public companies and general market conditions.

The Company's investment in Civitas Therapeutics, Inc. ("Civitas") was $0.8 million and $2.0 million at March 31, 2013 and 2012, respectively, which is recorded within "Other assets" in the accompanying consolidated balance sheets. The Company accounts for its investment in Civitas under the equity method as the Company has an approximately 11% ownership position in Civitas, has a seat on the board of directors and believes it may be able to exercise significant influence over the operating and financial policies of Civitas.

During the year ended March 31, 2012, Civitas issued 14.3 million shares of Series A preferred stock in exchange for $12.5 million. The Company did not participate in the financing, however, it received 12.4% of these Series A preferred shares in accordance with the terms of its arrangement with Civitas and recorded an increase to its investment in Civitas of $1.5 million. The Company has deferred the recognition of the gain on its investment in Civitas and will recognize it into "Other (expense) income, net", ratably over a period of approximately four years, in the Company's consolidated statement of operations and comprehensive income (loss). During the year ended March 31, 2013, the Company recorded a reduction in its investment in Civitas of $1.2 million, which represented the Company's proportionate share of Civitas' net losses for this period.

In December 2012, the Company and four other existing investors agreed to provide Civitas with a promissory note in the amount of $9.0 million. The promissory note will pay 6% interest per year, is payable on demand at any time on or after December 18, 2013, and is convertible into either common or preferred shares of Civitas upon a majority vote of the promissory note holders on or after December 18, 2013, or in the event of a qualified financing as defined in the Note Purchase Agreement. The Company's share of the promissory note, $1.1 million, was recorded within "Prepaid expenses and other current assets" in the accompanying consolidated balance sheets.