Stockholders' Equity	12 Months Ended
Dec. 31, 2020
Stockholders' Equity
Stockholders' Equity	16. Stockholders’ Equity Preferred Stock The Company has authorized 5.0 million shares of preferred stock, par value $0.01 per share. The Company’s certificate of incorporation provides that shares of preferred stock may be issued from time to time in one or more series. The Company’s Board of Directors is authorized to fix the voting rights, if any, designations, powers, preferences, qualifications, limitations and restrictions thereof, applicable to the shares of each series. The Company has authorized Series A Junior Participating Cumulative Preferred Stock, par value $0.01 per share. As of December 31, 2020 and December 31, 2019, there were no shares of Series A Junior Participating Cumulative Preferred Stock issued and outstanding. See Note 17, “Redeemable Convertible Preferred Stock,” for a description of the Company’s Series C Preferred Stock and Series E Preferred Stock. Common Stock and Warrants The Company has one class of common stock, par value $.01 per share. Each share of the Company’s common stock is entitled to one vote on all matters submitted to stockholders. In February 2021, the Company completed the previously announced sale of its common stock in connection with a strategic partnership with SK Holdings to accelerate the use of hydrogen as an alternative energy source in Asian markets. The Company sold 54,966,188 shares of its common stock to a subsidiary of SK Holdings at a purchase price of $29.2893 per share, or an aggregate purchase price of approximately $1.6 billion. In January and February 2021, the Company issued and sold in a registered equity offering an aggregate of 32.2 million shares of its common stock at a purchase price of $65.00 per share for net proceeds of approximately $1.8 billion. See Note 23, “Subsequent Events,” for more information. In November 2020, the Company issued and sold in a registered direct offering an aggregate of 43,700,000 shares of its common stock at a purchase price of $22.25 per share for net proceeds of approximately $927.3 million. In August 2020, the Company issued and sold in a registered direct offering an aggregate of 35,276,250 shares of its common stock at a purchase price of $10.25 per share for net proceeds of approximately $344.4 million. In December 2019, the Company issued and sold in a registered public offering an aggregate of 46 million shares of its common stock at a purchase price of $2.75 per share for net proceeds of approximately $120.4 million. In March 2019, the Company issued and sold in a registered direct offering an aggregate of 10 million shares of its common stock at a purchase price of $2.35 per share. The net proceeds to the Company were approximately $23.5 million. There were 458,051,920 and 303,378,515 shares of common stock outstanding as of December 31, 2020 and December 31, 2019, respectively. During 2017, warrants to purchase up to 110,573,392 shares of common stock were issued in connection with transaction agreements with Amazon and Walmart, as discussed in Note 18, “Warrant Transaction Agreements.” At December 31, 2020 and December 31, 2019, 68,380,913 and 26,188,434 of the warrant shares had vested, respectively, and are therefore exercisable. These warrants are measured at fair value at the time of grant or modification and are classified as equity instruments on the consolidated balance sheets. Refer to Note 23, “Subsequent Events.” At Market Issuance Sales Agreement On April 13, 2020, the Company entered into the At Market Issuance Sales Agreement with B. Riley Financial (“B. Riley”) as sales agent, pursuant to which the Company may offer and sell, from time to time through B. Riley, shares of Company common stock having an aggregate offering price of up to $75.0 million. As of the date of this filing, the Company has not issued any shares of common stock pursuant to the At Market Issuance Sales Agreement. Prior to December 31, 2019, the Company entered into a previous At Market Issuance Sales Agreement with B. Riley, which was terminated in the fourth quarter of 2019. Under this At Market Issuance Sales Agreement, for the year ended December 31, 2019, the Company issued 6.3 million shares of common stock, resulting in net proceeds of $14.5 million and for the year ended December 31, 2018, the Company issued 3.8 million shares of common stock, resulting in net proceeds of $7.0 million.

Stockholders' Equity

12 Months Ended

Dec. 31, 2020

16. Stockholders’ Equity

Preferred Stock

The Company has authorized 5.0 million shares of preferred stock, par value $0.01 per share. The Company’s certificate of incorporation provides that shares of preferred stock may be issued from time to time in one or more series. The Company’s Board of Directors is authorized to fix the voting rights, if any, designations, powers, preferences, qualifications, limitations and restrictions thereof, applicable to the shares of each series.

The Company has authorized Series A Junior Participating Cumulative Preferred Stock, par value $0.01 per share. As of December 31, 2020 and December 31, 2019, there were no shares of Series A Junior Participating Cumulative

Preferred Stock issued and outstanding. See Note 17, “Redeemable Convertible Preferred Stock,” for a description of the Company’s Series C Preferred Stock and Series E Preferred Stock.

Common Stock and Warrants

The Company has one class of common stock, par value $.01 per share. Each share of the Company’s common stock is entitled to one vote on all matters submitted to stockholders.

In February 2021, the Company completed the previously announced sale of its common stock in connection with a strategic partnership with SK Holdings to accelerate the use of hydrogen as an alternative energy source in Asian markets. The Company sold 54,966,188 shares of its common stock to a subsidiary of SK Holdings at a purchase price of $29.2893 per share, or an aggregate purchase price of approximately $1.6 billion.

In January and February 2021, the Company issued and sold in a registered equity offering an aggregate of 32.2 million shares of its common stock at a purchase price of $65.00 per share for net proceeds of approximately $1.8 billion. See Note 23, “Subsequent Events,” for more information.

In November 2020, the Company issued and sold in a registered direct offering an aggregate of 43,700,000 shares of its common stock at a purchase price of $22.25 per share for net proceeds of approximately $927.3 million.

In August 2020, the Company issued and sold in a registered direct offering an aggregate of 35,276,250 shares of its common stock at a purchase price of $10.25 per share for net proceeds of approximately $344.4 million.

In December 2019, the Company issued and sold in a registered public offering an aggregate of 46 million shares of its common stock at a purchase price of $2.75 per share for net proceeds of approximately $120.4 million.

In March 2019, the Company issued and sold in a registered direct offering an aggregate of 10 million shares of its common stock at a purchase price of $2.35 per share. The net proceeds to the Company were approximately $23.5 million.

There were 458,051,920 and 303,378,515 shares of common stock outstanding as of December 31, 2020 and December 31, 2019, respectively.

During 2017, warrants to purchase up to 110,573,392 shares of common stock were issued in connection with transaction agreements with Amazon and Walmart, as discussed in Note 18, “Warrant Transaction Agreements.” At December 31, 2020 and December 31, 2019, 68,380,913 and 26,188,434 of the warrant shares had vested, respectively, and are therefore exercisable. These warrants are measured at fair value at the time of grant or modification and are classified as equity instruments on the consolidated balance sheets. Refer to Note 23, “Subsequent Events.”

At Market Issuance Sales Agreement

On April 13, 2020, the Company entered into the At Market Issuance Sales Agreement with B. Riley Financial (“B. Riley”) as sales agent, pursuant to which the Company may offer and sell, from time to time through B. Riley, shares of Company common stock having an aggregate offering price of up to $75.0 million. As of the date of this filing, the Company has not issued any shares of common stock pursuant to the At Market Issuance Sales Agreement.

Prior to December 31, 2019, the Company entered into a previous At Market Issuance Sales Agreement with B. Riley, which was terminated in the fourth quarter of 2019. Under this At Market Issuance Sales Agreement, for the year ended December 31, 2019, the Company issued 6.3 million shares of common stock, resulting in net proceeds of $14.5 million and for the year ended December 31, 2018, the Company issued 3.8 million shares of common stock, resulting in net proceeds of $7.0 million.