11. Stock-Based Compensation

Equity Incentive Plans

In November 2011, the Company established the 2011 Employee, Director and Consultant Equity Incentive Plan (the “2011 Plan”) and reserved shares of the Company’s common stock for sale and issuance under the 2011 Plan. Options granted under the 2011 Plan generally vest over a four-year period and generally expire ten years from the date of grant. Options are exercisable only to the extent vested. The 2011 Plan terminated in November 2021, and accordingly, no additional shares are available for grant under the 2011 Plan. The 2011 Plan continues to govern outstanding awards granted under the 2011 Plan.

The 2021 Equity Incentive Plan (the “2021 Plan”) was established in July 2021. The 2021 Plan provides for the grant of incentive and non-statutory stock options as well as other stock rights to employees, directors and consultants of the Company. Options generally vest over a four-year period, are exercisable only to the extent vested, and generally expire ten years from the date of grant. Restricted stock units (“RSUs”) generally vest over either a two-year or a four-year period. The 2021 Plan includes provisions for annual automatic increases to the number of shares of Class A common stock reserved for issuance under the 2021 Plan. In addition, any shares that otherwise would be returned to the 2011 Plan as a result of the expiration or cancellation of stock options may be added to the 2021 Plan. As of December 31, 2025, there were 1,581,152 shares of the Company’s Class A common stock that were available for future grants under the 2021 Plan.

The 2021 Employee Stock Purchase Plan (the “2021 ESPP”) was established in July 2021. The 2021 ESPP includes provisions for annual automatic increases to the number of shares of Class A common stock reserved for issuance under the 2021 ESPP. As of December 31, 2025, there were 1,315,291 shares of the Company’s Class A common stock that were available for future grants under the 2021 ESPP.

Stock Options

Unless otherwise noted, references to “options” in the subsequent disclosures, refers to the combined incentive and non-statutory stock options issued as employee and non-employee stock-based compensation, and authorized under the 2011 Plan and the 2021 Plan. The following table summarizes information about these options granted and outstanding:

 

 

 

Number of
Shares
Subject to
Options
Outstanding

 

 

Weighted-
Average
Exercise
Price Per
Share

 

 

Weighted-
Average
Remaining
Contractual
Life (In
Years)

 

 

Aggregate
Intrinsic
Value (In
Thousands)

 

Outstanding – December 31, 2024

 

 

6,113,155

 

 

$

3.91

 

 

 

6.3

 

 

$

27,008

 

Granted

 

 

888,957

 

 

 

3.27

 

 

 

 

 

 

 

Expired

 

 

 

 

 

 

 

 

 

 

 

 

Cancelled

 

 

(169,216

)

 

 

5.60

 

 

 

 

 

 

 

Exercised

 

 

(308,617

)

 

 

1.64

 

 

 

 

 

 

 

Outstanding – December 31, 2025

 

 

6,524,279

 

 

$

3.88

 

 

 

5.8

 

 

$

3,353

 

Vested and expected to vest at December 31, 2025

 

 

6,386,136

 

 

$

3.89

 

 

 

5.8

 

 

$

3,327

 

Vested and exercisable at December 31, 2025

 

 

5,673,516

 

 

$

3.95

 

 

 

5.4

 

 

$

3,135

 

 

The weighted-average grant date fair value of options granted during the years ended December 31, 2025 and 2024 was $2.13 and $5.54 per share, respectively. The total aggregate intrinsic value of options exercised during the years ended December 31, 2025 and 2024 was $0.5 million and $5.5 million, respectively. The total fair value of options vested for the years ended December 31, 2025 and 2024 was $2.2 million and $3.7 million, respectively.

The fair values calculated using the Black-Scholes option pricing model were estimated on each grant date using the following assumptions:

 

 

 

Year Ended

 

 

 

December 31,

 

 

 

2025

 

 

2024

 

Expected volatility

 

69.9% - 70.4%

 

 

78.8% - 78.9%

 

Risk-free interest rate

 

3.7% - 4.1%

 

 

4.1% - 4.2%

 

Expected term (in years)

 

5.3 - 6.1

 

 

5.2 - 5.3

 

Expected dividend yield

 

 

0

%

 

 

0

%

 

RSUs

The following table summarizes information about RSUs granted and outstanding under the 2021 Plan:

 

 

 

Number of Awards

 

 

Weighted-Average
Grant Date Fair
Value

 

Outstanding – December 31, 2024

 

 

1,631,162

 

 

$

2.60

 

Granted

 

 

1,182,889

 

 

 

3.49

 

Forfeited

 

 

(84,008

)

 

 

3.96

 

Vested

 

 

(1,259,167

)

 

 

2.57

 

Outstanding – December 31, 2025

 

 

1,470,876

 

 

$

3.27

 

 

 

Stock-Based Compensation Expense

The following table presents the impact of stock-based compensation expense in the statements of operations for the periods indicated (in thousands):

 

 

 

Year Ended

 

 

 

December 31,

 

 

 

2025

 

 

2024

 

Research and development expense

 

$

1,746

 

 

$

2,502

 

Selling and marketing expense

 

 

314

 

 

 

390

 

General and administrative expense

 

 

3,050

 

 

 

4,121

 

Total employee stock-based compensation

 

$

5,110

 

 

$

7,013

 

 

The information about unrecognized stock-based compensation expense for outstanding unvested stock options and RSUs as of December 31, 2025 was as follows (in thousands, except years):

 

 

 

Unrecognized
Stock-Based
Compensation
Expense

 

 

Weighted-Average
Period of
Recognition
(in years)

 

Stock Options

 

$

1,498

 

 

 

2.6

 

RSUs

 

 

3,561

 

 

 

2.7

 

Total unrecognized stock-based compensation expense

 

$

5,059

 

 

 

 

Historical Timeline

Fiscal YearFiled
2025Mar 18, 2026Showing above
2024Mar 19, 2025
2022Mar 22, 2023

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.