Shares of easyJet dropped sharply following reports that the European Union is preparing to review its rules on airline ownership, raising uncertainties about the planned £5.7 billion acquisition of the low-cost carrier by US asset manager Apollo Global Management.

The EU intends to clarify the provisions governing foreign investor control over airlines to safeguard the bloc’s “strategic autonomy,” according to a European official. This development complicates a prolonged takeover process for easyJet, whose board recently endorsed Apollo’s higher offer, surpassing an earlier £5.5 billion bid from US private credit firm Castlelake.

Following the news, easyJet’s stock fell as much as 14 percent before regaining some ground to close down 12 percent. The current regulatory framework requires that airlines operating within the EU must be majority-owned and controlled by EU member states or their nationals. This means they must have decisive influence over the carrier’s operations. Although the United Kingdom has left the bloc, easyJet remains subject to the rules through its Austrian subsidiary, which it uses to continue offering flights within Europe.

Similar EU restrictions have already affected other industry deals, such as the withdrawal of International Airlines Group (IAG) from an attempt to acquire 80 percent of Spanish carrier Air Europa in early 2024, following competition concerns raised by the European Commission.

Industry figures have expressed skepticism about the prospects of the easyJet takeover navigating these regulations. Luis Gallego, CEO of International Airlines Group, described the acquisition as potentially “very, very difficult” due to the ownership rules. Willie Walsh, head of the International Air Transport Association (IATA) and former IAG CEO, noted that airlines already face “some of the most stringent ownership rules,” and any changes to these regulations should be made after consulting carriers that have structured their businesses accordingly.

Both easyJet and Apollo declined to comment on the reported review, and Castlelake did not immediately respond to requests for comment. A source close to the airline indicated that EU regulators have not formally engaged with easyJet regarding the proposed bids by Apollo or Castlelake. The outcome of the EU’s evaluation remains uncertain as the bloc moves to reinforce oversight of foreign investment in its aviation sector.