A round-up of UK competition law developments, including (amongst other things) (1) the CMA decides that the partnership between Microsoft Corporation and OpenAI, Inc. does not qualify for investigation under the merger provisions of the Enterprise Act 2002, and (2) the Court of Appeal dismisses appeal relating to its first judgment on the UK’s post-Brexit subsidy regime, and (2) CAT issues judgment dismissing jurisdictional challenge in damages action brought by supermarkets against salmon suppliers.