Financial Instruments

6 Months Ended

Jun. 30, 2011

Financial Instruments [Abstract]

Financial Instruments

Note 2. Financial Instruments

     The following table summarizes the fair value of our cash, cash equivalents and available-for-sale marketable securities held in our current investment portfolio:

			Gross		Gross
	Amortized		Unrealized		Unrealized
	Cost		Gains		(Losses)			Fair Value
June 30, 2011
Cash	$	846,396	$	—	$	—		$	846,396
Cash equivalents		5,687,249		—		—			5,687,249
Marketable debt securities, current		9,125,333		—		(2,145	)		9,123,188
Total cash, cash equivalents, and marketable securities	$	15,658,978		—	$	(2,145	)	$	15,656,833
December 31, 2010
Cash	$	1,001,868	$	—	$	—		$	1,001,868
Cash equivalents		18,705,953		—		—			18,705,953
Marketable equity securities, current		74,456		116,348		—			190,804
Total cash, cash equivalents, and marketable securities	$	19,782,277	$	116,348	$	—		$	19,898,625

     Gross unrealized gains and losses on cash equivalents were not significant at June 30, 2011 and December 31, 2010. At June 30, 2011, our cash equivalents were primarily money market funds consisting mainly of U.S. Treasury debt securities.

     Our investment in marketable debt securities, are short term investments that consist primarily of commercial paper and corporate debt securities,

     Our investment in marketable equity securities consists of ordinary shares of ReNeuron Group Plc (ReNeuron), a publicly listed U.K. corporation. In July 2005, we entered into an agreement with ReNeuron under which we granted ReNeuron a license that allows ReNeuron to exploit its “c-mycER” conditionally immortalized adult human neural stem cell technology for therapy and other purposes. We received shares of ReNeuron common stock, as well as a cross-license to the exclusive use of ReNeuron’s technology for certain diseases and conditions, including lysosomal storage diseases, spinal cord injury, cerebral palsy, and multiple sclerosis. The agreement also provides for full settlement of any potential claims that either we or ReNeuron might have had against the other in connection with any putative infringement of certain of each party’s patent rights prior to the effective date of the agreement. In July and August 2005, we received approximately 8,836,000 ordinary shares of ReNeuron common stock, net of approximately 104,000 shares that were transferred to NeuroSpheres, Ltd., an Alberta corporation (NeuroSpheres), and subsequently, as a result of certain anti-dilution provisions in the agreement, we received approximately 1,261,000 more shares, net of approximately 18,000 shares that were transferred to NeuroSpheres. In February 2007, we sold 5,275,000 shares for net proceeds of approximately $3,075,000. We recognized approximately $716,000 as realized gain from this transaction. In the first quarter of 2009, we sold 2,900,000 shares of ReNeuron and received net proceeds of approximately $510,000 for a realized gain of approximately $398,000. In the second quarter of 2011, we sold our remaining 1,921,924 shares of ReNeuron and received net proceeds of approximately $158,000 for a realized gain of approximately $84,000. As of June 30, 2011, we no longer hold any shares of ReNeuron.