This article considers the implications of the unusual validating provisions in the Financial Services Bill (HL Bill 162), which retrospectively validate the Financial Collateral Arrangements (No 2) Regulations 2003 (SI 2003/3226) notwithstanding any lack of power to make the Regulations, in circumstances where the Regulations give effect to EU Directive 2002/47/EC. It examines the critical questions that would have arisen pre-Brexit, and those that now arise, in relation to whether such validating legislation is lawful and argues that such validation is likely to be effective post-Brexit.