13. Stockholders’ equity

At December 31, 2018 and 2017, we are authorized to issue up to 100,000,000 shares of common stock. We are required to reserve and keep available out of our authorized but unissued shares of common stock such number of shares sufficient to effect the exercise of all outstanding common stock warrants, plus shares granted and available for grant under our Amended and Restated 2001 Stock Incentive Plan (the “2001 Plan”) and 2011 Equity Incentive Plan (the “2011 Plan”), as amended. Refer to Note 17 for a discussion of the 2011 Plan amendments.

The amount of such shares of common stock reserved for these purposes is as follows:


	December 31,
	2018	2017
	(in thousands)
Outstanding stock options under the 2001 Plan	14	155
Outstanding stock options under the 2011 Plan	290	1,128
Outstanding RSUs under the 2011 Plan	3,119	3,324
Shares available for grant under the 2011 Plan	2,979	3,863
Total	6,402	8,470

The Convertible Notes have an initial conversion rate of 23.6323 shares of common stock per $1,000 principal amount of the Convertible Notes, which will be subject to customary anti-dilution adjustments in certain circumstances. The amount of shares that would be issuable assuming conversion of all of the Convertible Notes is approximately 4,756,000.