The Competition Commission has given the green light for Euronext and Deutsche Börse to bid for the London Stock Exchange (LSE), but imposed some tough conditions that many believe are potential deal-breakers. Following a seven-month inquiry, the commission found that both bids would "substantially lessen competition" and ruled that the deals would only get the go-ahead if the buyers agreed to reduce their control over the LSE's clearing house after a merger. The commission believes the bidders' control over share clearing would make it difficult for rival exchanges to compete with the LSE. Euronext, advised by Cleary Gottlieb Steen & Hamilton and Slaughter and May, will decide whether to proceed within two months. Several sources close to the deal expect Euronext to withdraw. Deutsche Börse, advised by Ashurst and Goldman Sachs, said it welcomed the commission's decisions and that the conditions would not impact on its business. Freshfields Bruckhaus Deringer is advising the LSE.