Ambiq Micro, Inc. Stock Compensation Disclosure
12. Stock Option Plan and Stock-Based Compensation
Summary of Stock-Based Compensation Expense
The following table summarizes the effects of stock-based compensation on cost of sales, research and development, and sales, general and administrative expenses granted under the Plans (in thousands) for the years ended December 31, 2025 and 2024, respectively:
|
|
2025 |
|
|
2024 |
|
||
Cost of sales |
|
$ |
227 |
|
|
$ |
356 |
|
Research and development |
|
|
2,589 |
|
|
|
2,416 |
|
Sales, general and administrative |
|
|
4,019 |
|
|
|
2,402 |
|
Total |
|
$ |
6,835 |
|
|
$ |
5,174 |
|
In July 2025, the Company's board of directors adopted, and the Company's stockholders approved the 2025 Equity Incentive Plan (the 2025 Plan). The 2025 Plan became effective on July 29, 2025. No further awards will be granted under the 2010 Equity Incentive Plan (2010 Plan) or 2020 Equity Incentive Plan (2020 Plan, and collectively, along with the 2025 Plan and 2010 Plan, the Plans).
Awards outstanding under the Plans remain subject to the terms of the respective Plans, but shares reserved for issuance under each of the 2010 Plan and 2020 Plan that were not subject to outstanding awards at the time the 2025 Plan became effective are no longer available for issuance.
The following table summarizes the activity in total shares of common stock available for issuance under the 2010 and 2020 Plans, reflecting the impact of the Stock Split:
|
|
Shares |
|
|
Balance, January 1, 2024 |
|
|
421,280 |
|
Shares added |
|
|
625,571 |
|
Granted |
|
|
(680,690 |
) |
Forfeited |
|
|
31,493 |
|
Balance, December 31, 2024 |
|
|
397,654 |
|
Shares added |
|
|
— |
|
Granted |
|
|
(236,785 |
) |
Forfeited |
|
|
32,793 |
|
Cancelled |
|
|
(193,662 |
) |
Balance, December 31, 2025 |
|
|
— |
|
The following table summarizes the activity in total shares available for issuance under the 2025 Plan:
|
|
Shares |
|
|
Balance, January 1, 2024 |
|
|
— |
|
Shares added |
|
|
— |
|
Granted |
|
|
— |
|
Forfeited |
|
|
— |
|
Balance, December 31, 2024 |
|
|
— |
|
Shares added |
|
|
1,703,600 |
|
Granted |
|
|
(1,364,422 |
) |
Forfeited |
|
|
52,329 |
|
Balance, December 31, 2025 |
|
|
391,507 |
|
Stock Options
The fair value for the Company’s options was estimated at the date of grant using a Black-Scholes option pricing model with the following weighted-average assumptions:
|
|
Years Ended December 31, |
|
|||||
|
|
2025 |
|
|
2024 |
|
||
Risk-free interest rate |
|
|
4.16 |
% |
|
|
4.16 |
% |
Expected life of the options |
|
6.07 years |
|
|
5.47 years |
|
||
Dividend rate |
|
|
0 |
% |
|
|
0 |
% |
Volatility |
|
|
64.16 |
% |
|
|
54.51 |
% |
Fair value per share of common stock |
|
$ |
16.80 |
|
|
$ |
12.60 |
|
Additional information regarding outstanding options that are vesting, expected to vest, or exercisable as of December 31, 2025, is as follows:
|
|
Number |
|
|
Weighted- |
|
|
Weighted- |
|
|
Weighted- |
|
||||
Options outstanding at December 31, 2023 |
|
|
1,760,984 |
|
|
$ |
7.28 |
|
|
$ |
14.84 |
|
|
|
6.03 |
|
Options granted |
|
|
1,377,527 |
|
|
$ |
10.58 |
|
|
$ |
12.58 |
|
|
|
— |
|
Options exercised |
|
|
(78,374 |
) |
|
$ |
8.57 |
|
|
$ |
10.90 |
|
|
|
— |
|
Options forfeited |
|
|
(831,282 |
) |
|
$ |
0.47 |
|
|
$ |
22.95 |
|
|
|
— |
|
Options outstanding at December 31, 2024 |
|
|
2,228,855 |
|
|
$ |
7.83 |
|
|
$ |
10.65 |
|
|
|
6.23 |
|
Options granted |
|
|
165,349 |
|
|
$ |
10.47 |
|
|
|
17 |
|
|
|
|
|
Options exercised |
|
|
(117,955 |
) |
|
$ |
5.14 |
|
|
|
7 |
|
|
|
|
|
Options forfeited |
|
|
(34,639 |
) |
|
$ |
12.69 |
|
|
|
12 |
|
|
|
|
|
Options outstanding at December 31, 2025 |
|
|
2,241,610 |
|
|
$ |
8.10 |
|
|
$ |
11.27 |
|
|
|
5.72 |
|
Vested and expected to vest |
|
|
2,241,610 |
|
|
$ |
8.10 |
|
|
$ |
11.27 |
|
|
|
5.72 |
|
Exercisable |
|
|
1,935,280 |
|
|
$ |
7.97 |
|
|
$ |
10.81 |
|
|
|
5.24 |
|
The weighted-average fair value of options granted during the years ended December 31, 2025 and 2024, was $10.5 and $10.6 per share, respectively. The aggregate intrinsic value of options exercised during the years ended December 31, 2025 and 2024 was $2.4 million and $0.3 million, respectively. Intrinsic value represents the difference between the market value of the Company’s common stock at the time of exercise and the strike price of the stock option. The total unrecognized stock-based compensation expense related to unvested stock options and subject to recognition in future periods was approximately $2.4 million and $4.2 million at December 31, 2025 and 2024. As of December 31, 2025, the Company anticipates this expense to be recognized over a weighted-average period of approximately 1.6 years. During the year ended December 31, 2025, the Company's board of directors approved the acceleration of one-third of previously issued options to the Company's chief financial officer, resulting in an additional $0.5 million of stock-based compensation expense for the year ended December 31, 2025.
During the years ended December 31, 2025 and 2024, the Company received $0.8 million and $0.9 million, respectively, from the exercise of stock options granted under the Plans.
Restricted Stock Units
A summary of RSU activity under the 2020 and 2025 Plans are as follows:
|
|
Number |
|
|
Weighted-Average |
|
||||||
|
|
2020 Plan |
|
|
2025 Plan |
|
|
|
|
|||
RSUs outstanding at December 31, 2024 |
|
|
113,816 |
|
|
|
— |
|
|
$ |
15.36 |
|
RSUs granted |
|
|
71,427 |
|
|
|
1,364,422 |
|
|
$ |
28.82 |
|
RSUs cancelled and forfeited |
|
|
— |
|
|
|
(52,329 |
) |
|
$ |
29.68 |
|
RSUs outstanding at December 31, 2025 |
|
|
185,243 |
|
|
|
1,312,093 |
|
|
$ |
27.77 |
|
RSUs were granted under the 2020 Plan during the year ended December 31, 2025. Following the effective date of the 2025 plan, no additional grants will be made under the 2020 Plan.
The Company recognized approximately $0.7 million of share based compensation expense during the year ended December 31, 2025, related to RSUs in which the time-based service and performance conditions were satisfied upon completion of the IPO. This expense was reflected in sales, general and administrative expense.
The total unrecognized stock-based compensation expense related to unvested RSUs in future periods was approximately $38.0 million and $1.7 million at December 31, 2025 and 2024. As of December 31, 2025, the Company anticipates this expense to be recognized over a weighted-average period of approximately 3.7 years.
During the years ended December 31, 2025 and 2024, the Company granted 1,435,849 and 2,666,664 RSUs, respectively, to several directors and employees. 44,822 of these RSUs vested upon completion of the IPO.
About Stock Compensation Disclosures
Stock-based compensation disclosures detail the equity awards granted to employees and executives — including stock options, restricted stock units (RSUs), and performance shares — along with the valuation methods and assumptions used to expense them. This section reveals the true cost of talent retention and the alignment between management incentives and shareholder interests.
Key signals: total unrecognized compensation expense and its expected recognition period signal future earnings headwinds from already-granted awards. For stock options, examine Black-Scholes assumptions — expected volatility, risk-free rate, and expected term — as understating any of these reduces reported compensation expense. Compare stock compensation expense as a percentage of revenue against peers to assess dilution cost. Watch vesting schedules for acceleration clauses tied to change-of-control events. Performance-based awards with undemanding targets may indicate weak governance. Add back stock compensation to operating cash flow to calculate a more conservative free cash flow figure.