Set it below value and the holder can lose a deduction and pick up an immediate taxable benefit; set it far above value and the option is worth nothing as an incentive. Early on the value is nominal and the board’s resolution says so; after a financing, the round price is the evidence, and a valuation may be needed.
For a Canadian-controlled private corporation the tax works in the holder’s favour in general terms: an employee is usually taxed on the option only when the shares are sold rather than when the option is exercised, and a deduction may reduce the tax where the conditions are met, one of which is holding the shares for two years. Options from a company that is not a CCPC are taxed at exercise, with a deduction subject to limits. The plan is drafted to keep those benefits available; whether they apply to your company and each holder is your accountant’s call, and the scope review asks whether they have looked. Grants to employees, officers, directors and consultants also rely on a prospectus exemption under Ontario securities law that usually needs no report, and the plan confirms it.