13Share-based compensation

Share option and restricted share unit plans

2014 Incentive Plan

On July 23 2014, the Company’s board of directors and shareholders approved the 2014 Incentive Plan (the “2014 Plan”). Awards under the 2014 Plan vest up to 4 years from the date of grant and expire no more than 10 years after the grant date. The Company reserved a total of 5,500,000 common shares for issuance under the 2014 Plan. As of December 31, 2025, there were no shares remain available for grant under the 2014 Plan as the 2014 Plan has expired. For the years ended December 31, 2025, the Company has extended the terms of 306,828 awards that have been vested but not exercised under the 2014 Plan for additional periods. The impact of this modification is not significant.

2017 Incentive Plan

On March 1, 2017, the Company’s board of directors and shareholders approved the 2017 Incentive Plan (the “2017 Plan”). Awards under the 2017 Plan vest up to 4 years from the date of grant and expire no more than 10 years after the grant date. The Company reserved a total of 6,015,137 common shares for issuance under the 2017 Plan. As of December 31, 2025, 2,867 shares remain available of grant under the 2017 Plan.

2021 Incentive Plan

In December 2021, the Company’s board of directors and shareholders approved the 2021 Incentive Plan (the “2021 Plan”). Awards under the 2021 Plan vest up to 4 years from the date of grant and expire no more than 10 years after the grant date. The Company reserved a total of 4,000,000 common shares for issuance under the 2021 Plan. As of December 31, 2025, 1,960 shares remain available of grant under the 2021 Plan.

2023 Incentive Plan

In September 2023, the Company’s board of directors and shareholders approved the 2023 Incentive Plan (the “2023 Plan”). Awards under the 2023 Plan vest up to 4 years from the date of grant and expire no more than 10 years after the grant date. The Company reserved a total of 4,000,000 common shares for issuance under the 2023 Plan. As of December 31, 2025, 2,439,067 shares remain available of grant under the 2023 Plan.

The exercise price, vesting and other conditions of individual awards are determined by the board of directors or any of the committees appointed by the board of directors to administer the 2014, 2017, 2021 and 2023 Incentive Plans. Upon the termination of the Grantee’s continuous service, the Company has the right to repurchase the vested award or shares obtained.

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13Share-based compensation (continued)

Share option and restricted share unit plans (continued)

Share options

The following table summarizes the share option activity for the Company’s Incentive Plans for the year ended December 31, 2025:

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The aggregate intrinsic value in the table above represents the difference between the closing stock price on the last trading day in 2024 and 2025 and the option’s respective exercise price.

The weighted average grant date fair value of the share options granted during the years ended December 31, 2023, 2024 and 2025 were RMB3.23, RMB2.04 and RMB3.62 (US$0.52), respectively.

The aggregate unrecognized share-based compensation expense was RMB88 (US$13) as of December 31, 2025, which the Company expects to recognize over an estimated weighted-average period of 0.29 years.

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13Share-based compensation (continued)

Share option and restricted share unit plans (continued)

Share options (continued)

The Company estimates the fair value of each award on grant date using the binomial option pricing model. The binominal model requires the input of highly subjective assumptions, including the expected share price volatility and the suboptimal early exercise factor. For expected volatility, the Company has made reference to historical volatilities of several comparable companies. The suboptimal early exercise factor was estimated based on the Company’s expectation of exercise behavior of the grantees. The risk-free rate for periods within the contractual life of the options is based on the market yield of U.S. Treasury Bonds in effect at the time of grant. Subsequent to the IPO, fair value of the common shares is the price of the Company’s publicly traded shares. The Company’s management is ultimately responsible for the determination of the estimated fair value of its common shares.

The Company recognizes share-based compensation expense using the accelerated recognition method over the requisite service period, which is generally subject to graded vesting.

The following table presents assumptions used to estimate the fair values of share options granted for the years ended December 31, 2023, 2024 and 2025:

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13Share-based compensation (continued)

Share option and restricted share unit plans (continued)

Restricted share units

Starting from 2018, the Company granted restricted Class A common shares of the Company (“Restricted Shares”).

A summary of the restricted share units for the year ended December 31, 2025 was stated below:

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The weighted average grant-date fair value per restricted share unit granted for the years ended December 31, 2023, 2024 and 2025 were RMB1.74, RMB2.04 and RMB5.33 (US$0.76), respectively.

As of December 31, 2025, there was RMB837 (US$120) of unrecognized share-based compensation cost related to restricted shares units, which the Company expects to recognize over an estimated weighted-average period of 0.58 year.

The aggregate fair value of options and restricted share units vested and recognized as expenses for the years ended December 31, 2023, 2024 and 2025 were RMB11,574, RMB4,225 and RMB3,684 (US$527), respectively.

Total intrinsic value of options and restricted share units exercised/vested for the years ended December 31, 2023, 2024 and 2025 were RMB2,976, RMB5,796 and RMB4,734 (US$677), respectively.

Total compensation costs recognized for the years ended December 31, 2023, 2024 and 2025 were as follows:

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