This Practice Note covers the following topics: • legislation governing CSOPs—self-certification, registration and filing requirements • the HMRC approval process up to 6 April 2014 • the self-certification and registration regime since 6 April 2014 • self-certification—notice and timing • signing up for the self-certification regime • HMRC power to enquire into a CSOP • outcome of an HMRC enquiry • HMRC general power to require information • annual return filing requirements • common ERS annual return errors • penalties and appeals, and • amending annual returns For more general information regarding company share option plans (CSOPs), see Practice Note: How CSOPs work and key features. Legislation governing CSOPs—self-certification, registration and filing requirements The legislation governing the self-certification, registration and filing requirements for CSOPs is contained in paragraphs 28A–28K of Schedule 4, Part 7, and paragraph 33 of Schedule 4 Part 8 to the Income Tax (Earnings and Pensions) Act 2003 (ITEPA 2003). HMRC approval process up to 6 April 2014 Until 6 April 2014, in order to qualify