ERSM162545 | International from 6 April 2015: the relevant period - from 6 April 2015: securities acquired for less than market value pursuant to securities option
From HM Revenue & Customs · Employment Related Securities Manual
Where the securities in question were acquired by virtue of the exercise of a securities option, the relevant period:
begins with the day of the acquisition of the option, and
ends with the day the option vests
(Note: an option “vests” at the time it becomes exercisable, subject only to any period of time expiring (ITEPA03/S41G(11). See ERSM162565.)