11. Stockholders’ equity

Shares issued

During the nine months ended September 30, 2024, the Company issued 129,857 shares of common stock upon vesting of Restricted Stock Units ("RSUs") granted by the Company to management and employees, including 44,261 of reissued treasury stock. We withheld 52,252 shares to satisfy approximately $552,000 of employees’ tax obligations during the nine months ended September 30, 2024. We treat shares of common stock withheld for tax purposes on behalf of our employees in connection with the vesting of RSUs in a similar manner as common stock repurchases and reported as treasury stock. 

During the nine months ended September 30, 2024, the Company issued 20,111 shares of common stock for consulting services.

During the nine months ended September 30, 2024, the Company issued 7,330 shares of common stock upon vesting of RSUs granted to Board members.

During the nine months ended September 30, 2024, the Company issued 5,171 shares of common stock to Board members related to director fees.

During the nine months ended September 30, 2024, the Company issued 6,607 shares of common stock to a former employee related to a severance agreement.

During the nine months ended September 30, 2024, the Company issued 3,444 shares of common stock pursuant to the employee stock purchase plan.

During the nine months ended September 30, 2024, the Company issued 306,049 shares of common stock pursuant to the at the market issuance sales agreement for net proceeds of $2.8 million.

In May 2024, the Company completed a public offering of 1,006,250 shares of its common stock at the public offering price of $7.80 per share. In connection with the sale of common stock, the Company issued warrants to purchase shares of common stock at the rate of one warrant for every share of purchased common stock, at the offering price of $0.20 per warrant. After the deduction of the underwriter’s discount and expenses payable by us, we received net proceeds of $7.3 million. The Company used the relative fair value method to allocate the net proceeds of approximately $7.3 million between the common stock and the warrants. As presented below, the Company recorded the fair value of the warrants of $3.1 million and common stock of $4.2 million.

During the nine months ended  September 30, 2023, the Company issued 70,694 shares of common stock upon vesting of Restricted Stock Units ("RSUs") granted by the Company to management and employees, including 25,532 of reissued treasury stock. We withheld 46,960 shares to satisfy approximately $1,091,000 of employees’ tax obligations during the nine months ended  September 30, 2023. We treat shares of common stock withheld for tax purposes on behalf of our employees in connection with the vesting of RSUs in a similar manner as common stock repurchases and reported as treasury stock. 

During the nine months ended  September 30, 2023, the Company issued 6,546 shares of common stock upon vesting of RSUs granted to Board members.

During the nine months ended  September 30, 2023, the Company issued 789 shares of common stock to a former Board member to fulfill obligations related to consulting services.

During the nine months ended  September 30, 2023, the Company issued 4,231 shares of common stock to a Board member related to director fees.

During the nine months ended  September 30, 2023, the Company issued 23,468 shares of common stock upon the settlement of the securities class action lawsuit.

During the nine months ended  September 30, 2023, the Company issued 9,635 shares of common stock pursuant to the employee stock purchase plan.

In  July 2023, the Company completed a public offering of 909,650 shares of its common stock, for net proceeds of $18.3 million.

In  August 2023, the Company issued 227,273 shares of its common stock pursuant to that certain Securities Purchase Agreement (the “Yulho SPA”), with Yulho Co, Ltd., for net proceeds of $4.6 million.

During the nine months ended  September 30, 2023, the Company issued 162,215 shares of common stock pursuant to the At The Market Issuance Sales Agreement for net proceeds of $3.8 million.

Warrant issued

In connection with the above-described May 2024 public offering, the Company issued a warrant to purchase 39,125 shares of the Company's common stock to the underwriter of the Company's public offering, equal to 2% of the shares and the number of shares underlying the warrants sold in the offering, for relative fair value of $0.1 million. The warrants are exercisable at $9.75 per share on the closing date,  May 14, 2024. The warrants have an expiration date of 5 years from the date of issuance and will expire on  May 14, 2029. The relative fair value of the warrants was recorded in the condensed consolidated balance sheet in additional paid-in capital in stockholders' equity as the warrants are indexed to the Company’s common stock and meet the conditions for equity classification.

In May 2024, in conjunction with the Company's public offering, the Company issued a warrant to purchase up to 1,006,250 shares of the Company's common stock, for the relative fair value of $3 million. The warrants are exercisable at $7.80 per share. The warrants have an expiration date of 5 years from the date of issuance and will expire on May 14, 2029. The relative fair value of the warrants was recorded in the condensed consolidated balance sheet in additional paid-in capital in stockholders' equity as the warrants are indexed to the Company’s common stock and meet the conditions for equity classification.

In  July 2023, the Company issued a warrant to purchase 18,193 shares of the Company's common stock to the underwriter of the Company's public offering, equal to 2% of the 909,650 shares sold. The warrants are exercisable at $27.50 per share, commencing six months after  July 17, 2023. The warrants have an expiration date of 5 years from the date of issuance and will expire on   July 17, 2028.

In  August 2023, the Company issued a warrant to purchase 10,288 shares of the Company's common stock to the underwriter of the transaction in connection with the Yulho SPA. The warrants have an expiration date of 5 years from the date of issuance and are exercisable immediately at $25 per share. The warrant will expire on  August 4, 2028.

Stock-based compensation

The stock-based compensation expense was allocated as follows:

2019 Stock Incentive Plan

In 2019, our board of directors adopted the Aqua Metals, Inc. 2019 Stock Incentive Plan (the “2019 Plan”). On May 23, 2024, 475,000 shares of common stock was authorized and added to the plan. A total of 1,400,000 shares of common stock was authorized for issuance pursuant to the 2019 Plan. The 2019 Plan provides for the following types of stock-based awards: incentive stock options; non-statutory stock options; restricted stock; and performance stock. The 2019 Plan, under which equity incentives may be granted to employees and directors under incentive and non-statutory agreements, requires that the option price may not be less than the fair value of the stock at the date the option is granted. Option awards are exercisable until their expiration, which may not exceed 10 years from the grant date. As of  September 30, 2024, there were 570,743 remaining shares available for future grants.

Restricted stock units

During the first quarter of 2024, the Company granted 5,576 RSUs, all of which were subject to vesting, with a grant date fair value of $60,000 to employees. The shares vest in three equal installments over a three-year period.

During the second quarter of 2024, the Company granted 6,250 RSUs, all of which were subject to vesting, with a grant date fair value of $40,000 to employees. The shares vest in three equal installments over a three-year period.

During the third quarter of 2024, the Company granted 18,582 RSUs, all of which were subject to vesting, with a grant date fair value of $83,000 to Board Members. The shares vest in four equal installments with the first installment vesting immediately and the remaining three installments vesting over a nine-month period.

During the third quarter of 2024, the Company granted 20,111 RSUs, all of which were vested immediately, with a fair value of $150,000 for consulting fees.

During the third quarter of 2024, the Company granted 6,607 RSUs, all of which were vested immediately, with a fair value of $28,000 to an employee upon termination of a severance agreement.