Accounting policy
The grant-date fair value of share warrants, employee warrants, stock options and free shares granted to employees is recognized as a payroll expense with a corresponding increase in equity, over the vesting period. The amount recognized as an expense is adjusted to reflect the actual number of awards for which the related service conditions are expected to be met.
Determining the fair value of share-based awards at the grant date requires judgment, we use the Black-Scholes option-pricing model to determine the fair value of share options. The determination of the grant date fair value of options using an option-pricing model is affected by our ordinary share fair value as well as assumptions regarding a number of other complex and subjective variables. These variables include the fair value of our ordinary shares, the expected term of the options, our expected share price volatility, risk-free interest rates, and expected dividends, which are estimated as follows:
| • | Fair value of our ordinary shares. We use the closing sales price per ordinary share as quoted on Alternext market of Euronext in Paris on the grant date for Cellectis grants and valuations prepared by third parties for Calyxt grants. |
| • | Expected term. The expected term represents the period that our share-based awards are expected to be outstanding. As we do not have sufficient historical experience for determining the expected term of the ordinary share option awards granted, we have based our expected term on the simplified method, which represents the average period from vesting to the expiration of the award. |
| • | Expected volatility. For Cellectis grants, the expected share price volatility takes into account the Cellectis closing share prices and closing share price of industry peers for the remaining expected term of the ordinary share option grant. For the Calyxt grants, the expected volatility is based on comparable transactions method. |
| • | Risk-free rate. The risk-free interest rate is based on the yields of French government securities with maturities similar to the expected term of the options for each option group for Cellectis grants and US Treasury bonds for Calyxt grants. |
| • | Dividend yield. We have never declared or paid any cash dividends and do not presently plan to pay cash dividends in the foreseeable future. Consequently, we used an expected dividend yield of zero. |
Service and performance conditions attached to the transactions are not taken into account in determining fair value. If any of the assumptions used in the Black-Scholes model changes significantly, share-based compensation for future awards may differ materially compared with the awards granted previously.