Stockholders' Equity

12 Months Ended

Dec. 31, 2019

Common Stock

The following shares were reserved for future issuance:



	December 31, 2019
Common stock options outstanding and available for future grant	7,923,098
Warrants to purchase common stock	9,692,879
Employee Stock Purchase Plan	142,872
	17,758,849

Sale of Common Stock

In June 2019, the Company sold 2,415,000 shares of its common stock at a public offering price of $97.00 per share. After deducting underwriter discounts, commissions and offering expenses, the Company received net cash proceeds from the transaction of $219.9 million.

In January 2019, the Company sold 1,854,838 shares of its common stock at a public offering price of $62.00 per share. After deducting underwriter discounts, commissions and offering expenses, the Company received net cash proceeds from the transaction of $107.9 million.

In June 2018, the Company sold 3,162,500 shares of its common stock at a public offering price of $38.85 per share and sold warrants to purchase up to 421,650 shares of its common stock at a public offering price of $38.849 per warrant. After deducting underwriter discounts and offering expenses, the Company received net proceeds from the transaction of $130.7 million. The public offering price for the warrants was equal to the public offering price of the common stock, less the $0.001 per share exercise price of each warrant. The warrants were recorded as a component of stockholders’ equity within additional paid-in capital. Per their terms, the outstanding warrants to purchase shares of common stock may not be exercised if certain holders' ownership of the Company’s common stock would exceed 9.99% for certain holders, or 4.99% percent for other holders, following such exercise.

Disgorgement Proceeds

In January 2019, the Company received a payment of $1.1 million representing a disgorgement of short-swing profits from the sale of common stock by a beneficial owner pursuant to Section 16(b) of the Securities Exchange Act of 1934, as amended. The Company recognized these proceeds as a capital contribution from stockholders and reflected a corresponding increase to additional paid-in capital.

Warrants

As of December 31, 2019, the following warrants for common stock were issued and outstanding:



Issue date	Expiration date	Exercise price		Number of warrants outstanding
January 11, 2017	None	$	0.001	5,133,230
November 20, 2017	None	$	0.001	4,137,999
June 11, 2018	None	$	0.001	421,650
				9,692,879

During the year ended December 31, 2019, warrants for 2,125,033 shares of the Company's common stock were exercised via cashless exercises, resulting in the issuance of 2,125,000 shares of common stock.

During the year ended December 31, 2018, no warrants were exercised.

During the year ended December 31, 2017, warrants for 52,825 shares of the Company's common stock were exercised via cashless exercises and 585,729 shares were exercised for cash, generating proceeds of $4.6 million and resulting in the issuance of 638,554 shares of common stock.