Template:M summ Equity Derivatives 2.1
Commencement Date is relevant only for American Options — those which are exercisable at any time during their term,[1] of course, so you do need to know when the term starts — and indeed only appears once in the 2002 ISDA Equity Derivatives Definitions outside the actual definition in Section 2.1(a). I know what you are thinking, about the perfectly good trees that might be with us today.
The rest of these definitions are mechanical enough almost to go without saying — but that is not how ISDA’s crack drafting squad™ rolls, is it?
- ↑ To be contrasted with European Options, which are only exercisable on one day — usually expiry.