Note 7 - Common Stock

9 Months Ended

Sep. 30, 2014

Stockholders' Equity Note [Abstract]

Stockholders' Equity Note Disclosure [Text Block]

7.   Common Stock

At September 30, 2014, the Company had authorized 205,926,290 shares of Common Stock, $0.001 par value per share, of which 240,614 shares were issued and outstanding.  The Company has reserved for future issuances the following number of shares of Common Stock:

	September 30, 2014		December 31, 2013
Conversion of Series A Preferred Stock		1,700,622		1,426,482
Conversion of Series A-1 Preferred Stock		838,101		687,395
Conversion of Series B Preferred Stock		1,610,383		1,307,771
Conversion of Series C Preferred Stock		1,361,809		1,105,907
Conversion of Series D Preferred Stock		3,327,894		-
Stock-based compensation awards		1,135,415		623,111
Warrants to purchase Common Stock		659,806		659,806
Total		10,634,030		5,810,472

Immediately prior to the closing of the Company’s IPO (see Note 11), 498,889 shares of Common Stock were issued upon the exercise of warrants with a weighted-average exercise price of $4.60 per share.