This is a requirement for everyone who studies at LSE.
If you are a current LSE student or a member of staff, proof of identity and eligibility to study/work in the UK is checked when you register for your main programme of study or when you start your employment. For LSE Alumni, this check is not current therefore we need to do this, each year, when you register for a non-degree modern language course. You can do this here: LSE Alumni eligibility to study in the UK