On 13 November 2024, the Supreme Court handed down its decision in Unite the Union and another v Tyne and Wear Passenger Transport Executive T/A Nexus. In a unanimous decision delivered by Lord Leggatt and Lady Simler in a joint judgment, the Supreme Court agreed with the Court of Appeal decision and dismissed the appeal from Nexus seeking rectification of a legally unenforceable collective agreement in relation to pay. However, unlike the Court of Appeal, which held that collective agreements cannot be rectified as they are legally unenforceable, the Supreme Court recognised that such agreements incorporated into employment contracts can be rectified as doing so would affect legal rights or obligations between employees and employers. While this was the position in this case, and rectification would have indirectly affected the employer and relevant employees, the claim for rectification from an employer needs to be brought against affected employees rather than the unions, and the court reasoned that making an order altering the legal rights of employees without giving them the opportunity to be heard would be contrary to the principles of procedural justice. The court also confirmed that although employment tribunals cannot make an order for rectification, where there is a relevant mistake, it can treat the document as having been rectified for the purpose of determining the parties’ legal rights, as is the approach in civil courts. Nicholas Chronias, Partner at DAC Beachcroft LLP, David Reade KC and Joseph Bryan, barristers at Littleton Chambers, and Jonathan Tuck, Partner at Baker McKenzie comment on the judgment.