Stockholders' equity

6 Months Ended

Jun. 30, 2023

Stockholders' Equity Note [Abstract]

Stockholders’ equity

Stockholders’ equity

Preferred stock

As of June 30, 2023, the Company had 25,000,000 shares of authorized preferred stock. No shares of preferred stock have been issued.

At-the-market ("ATM") equity offering program

In May 2020, the Company established an ATM equity offering program (the "2020 ATM"), pursuant to which it was able to offer and sell up to $100.0 million of its common stock from time to time at prevailing market prices. During the first quarter of 2022, the Company sold 11,740,210 shares of common stock under the 2020 ATM, resulting in net proceeds of $54.8 million. As of March 31, 2022, the 2020 ATM had been fully utilized.

In February 2022, the Company established a new ATM equity offering program (the "February 2022 ATM"), pursuant to which it was able to offer and sell up to $100.0 million of its common stock from time to time at prevailing market prices. During the six months ended June 30, 2022, the Company sold 11,334,657 shares of common stock under the February 2022 ATM, resulting in net proceeds of $45.8 million. During the first quarter of 2023, the Company sold 256,386 shares of common stock under the February 2022 ATM, resulting in net proceeds of $1.6 million. As of March 31, 2023, the February 2022 ATM had been fully utilized.

In November 2022, the Company established an additional ATM equity offering program (the "November 2022 ATM"), pursuant to which it is able to offer and sell up to $150.0 million of its common stock from time to time at prevailing market prices. During the six months ended June 30, 2023, the Company sold 14,208,145 shares of common stock under the November 2022 ATM, resulting in net proceeds of $92.2 million. As of June 30, 2023, approximately $55.9 million remained unsold and available for sale under the November 2022 ATM.

Warrants

In connection with a 2013 Series A-1 Preferred Stock issuance, the Company granted to certain investors warrants to purchase 129,491 shares of common stock. The warrants have a $0.05 per share exercise price and a contractual life of 10 years. The fair value of these warrants was recorded as a component of equity at the time of issuance. As of June 30, 2023, there were warrants to purchase 22,590 shares of common stock outstanding. During the six months ended June 30, 2023, there were no exercises of warrants in exchange for common stock.

Common stock

At the Company's 2022 Annual Meeting of Stockholders on June 9, 2022, the Company's stockholders approved an amendment to the Company’s Fifth Amended and Restated Certificate of Incorporation to increase the number of authorized shares of common stock, $0.0001 par value per share, from 175,000,000 to 350,000,000. This increase became effective upon filing of a Certificate of Amendment with the Secretary of State of the State of Delaware on June 9, 2022.

The holders of the common stock are entitled to one vote for each share held. Common stockholders are not entitled to receive dividends, unless declared by the Board of Directors of the Company (the "Board").

As of June 30, 2023 and December 31, 2022, there were 16,052,928 and 11,944,664, respectively, shares of common stock reserved for the exercise of outstanding stock options, restricted stock units ("RSUs") and warrants.

	June 30, 2023	December 31, 2022
Stock options	12,359,185	10,051,283
Restricted stock units	3,671,153	1,870,791
Warrants	22,590	22,590
	16,052,928	11,944,664