The Competition Appeal Tribunal (the CAT) has held that the OFT is “in time” to review the 2006 acquisition by Ryanair of a minority shareholding in rival Aer Lingus.

Ryanair initially acquired a minority shareholding in Aer Lingus and then mounted a public bid for the entire shareholding in October 2006. The Commission investigated the public bid at the time and decided, in June 2007, to prohibit the transaction. Aer Lingus appealed against the Commission's decision not to order Ryanair to divest its existing minority stake in Aer Lingus and separately, Ryanair also appealed on the grounds that the Commission should not have prohibited its public bid for the entire shareholding in Aer Lingus. In July 2010, the General Court ruled that the Commission did not have the ability to examine or require divestment of minority shareholdings that do not confer 'decisive influence' for the purposes of the EU Merger Regulation.

Subsequent to the General Court’s ruling, the OFT announced in September 2010 that it would carry out an investigation into the acquisition, and Ryanair argued that the investigation was time-barred. Following its review of Ryanair’s complaint as to the OFT’s jurisdiction, the CAT has held that the OFT had a duty, pending the ongoing EU appeal process, to wait before opening any investigation. Otherwise, the OFT would create a risk of inconsistent outcomes with ongoing EU cases and potential conflicts with the co-operation principles in the Treaty on the Functioning of the European Union. Ryanair says it will appeal against the decision of the CAT.