The substantial shareholdings exemption (SSE) provides an exemption from capital gains (and disallowance of capital losses) for disposals of shares by companies, on or after 1 April 2002, which meet certain requirements. The legislation was extended to certain business disposals by FA 2011, and the detailed conditions for exemption were considerably relaxed by F(No. 2)A 2017, with effect from 1 April 2017. The 2017 changes also introduced a new exemption for certain non-trading companies that are partly owned by qualifying institutional investors.