15.Share-based Compensation

In August 2012, the Group’s board of directors adopted the share incentive plan (“2012 Option Plan”). Under the 2012 Option Plan, the Group’s shareholders have authorized the issuance of up to 75,268,817 ordinary shares underlying all options (including incentive share options, or ISOs), restricted shares and restricted share units granted to a participant under the plan, or the awards. The 2012 Option Plan was amended in October 2012 to increase the maximum aggregate number of ordinary shares to 155,631,013 Shares. The 2012 Option Plan was amended in July 2014 to increase the maximum aggregate number of ordinary shares to 266,153,637 Shares.

In August 2018, the Group’s board of directors adopted the 2018 Share Incentive Plan (“2018 Plan”). The maximum aggregate number of shares which may be issued under the 2018 Plan shall initially be 2.0% of the total number of shares issued and outstanding immediately following the completion of IPO, plus an annual increase on the first day of each of the first five (5) complete fiscal years after the completion of IPO and during the term of this plan commencing with the fiscal year beginning January 1, 2019, by an amount equal to 2.0% of the total number of shares issued and outstanding on the last day of the immediately preceding fiscal year (excluding issued shares reserved for future option exercise and restricted share unit vesting).

Share Options

The options have a contractual term of ten years. The vesting date starts on the grant date or the commencement date of a participant’s employment agreement. The options vest 20% or 25% on each of the four or five anniversary dates of the vesting date and upon continued employment. In the event of termination of a participant’s employment, the unvested options shall be terminated immediately. The participant’s right to exercise the vested options shall be terminated 2 or 3 months after the termination of the employment.

The Group uses the binomial option pricing model and the following assumptions to estimate the fair value of the options at the date of granted. No options were granted during the years ended December 31, 2024 and 2025.

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The risk-free rate of interest is based on the US Treasury yield curve as of valuation date. Volatility is estimated based on annualized standard deviation of daily stock price return of comparable companies for the period before valuation date and with similar span as the expected expiration term. The Group has never declared or paid any cash dividends on its capital stock, and the Group does not anticipate any dividend payments in the foreseeable future.

A summary of the aggregate option activity and information regarding options outstanding as of December 31, 2025 is as follows:

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15.Share-based Compensation (Continued)

Share Options (Continued)

The weighted average grant date fair values of options granted during the year ended December 31, 2022 were US$0.01, respectively. No options were granted during the years ended December 31, 2024 and 2025.

For the year ended December 31, 2022, 2,097,750 of options were exercised with an aggregate intrinsic value of US$145. For the years ended December 31, 2024 and 2025, no options were exercised.

For the years ended December 31, 2023, 2024 and 2025, the Group recognized share-based compensation expense of US$704,462, US$134,560 and US$37,725, respectively. As of December 31, 2025, there was no unrecognized compensation cost related to non-vested stock options.

Restricted Share Units

In 2023, 2024 and 2025, the Group granted no Restricted Share Units (“RSUs”). The RSUs have a contractual term of ten years and vest 25% on each anniversary over four years from the grant date. The vesting of these RSUs is conditioned on continued employment. Compensation expense based on fair value is amortized over the requisite service period of award using the straight line vesting attribution method.

A summary of the RSUs activity for the year ended December 31, 2025 is as follows:

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The share-based compensation expense related to RSUs of US$103, nil and nil were recognized by the Group for the years ended December 31, 2023, 2024 and 2025, respectively.

As of December 31, 2025, there was no unrecognized compensation costs, net of actual forfeitures, related to unvested restricted shares.