On 4 January 2022, UK CMA issued revised CMA2 guidance to reflect changes to the Enterprise act 2002 brought about by the National security and investment act 2021.

• In accordance with National Security and Investment Act 2021, s 62 and associated commencement no. 2 regulations, the previous statutory framework and guidance continues to apply in all ongoing cases, i.e. phase 1 or 2 investigation has commenced.
• In cases where secretary of State issued a public interest intervention notice (PIIN).
• And in future cases where a trigger event, under the 2021 act, occurs prior to 4 January 2022, in relation to which the secretary of State issues a PIIN after 4 January 2022.
• Revised guidance applies in relation to all other mergers from 4 January 2022 onwards.