AIRPORT operator BAA won an appeal against the Competition Commission yesterday, a development that may help it delay the sale of terminals in London and Scotland.

A tribunal unanimously decided there was “a real possibility of bias” in the commission’s March ruling that BAA should sell three of its seven airports within two years to open the field to competitors.

The regulator had ordered BAA to sell Gatwick, Stansted and either Glasgow or Edinburgh to weaken its hold on Britain’s airports. The firm sold Gatwick, the UK’s second busiest airport, to private equity group Global Infrastructure Partners for £1.5bn in October.

However, the Competition Appeals Tribunal yesterday upheld an appeal lodged by BAA in May which argued that a member of the commission’s decision-making committee, Professor Peter Moizer of Leeds University, was affected by “apparent bias”. As well as serving on the six-person panel Moizer was a strategic adviser to the Greater Manchester Pension Fund, which joined a consortium bidding for Gatwick including Manchester Airports Group.

Moizer confirmed to City A.M. that he met with the pension fund’s advisory panel eight times between the start of the Competition Commission’s investigation into BAA in March 2007 and its judgment in March 2009. “My involvement was declared at the start of the inquiry,” Moizer said, although he declined to comment further.

An investment officer at the Greater Manchester Pension fund played down the link between the retirement scheme and Manchester Airports Group. Steven Turner said: “The airport has its own strategy as a business and it’s not something we’re party to in the pension fund.”

The Competition Commission said it was “disappointed” with the tribunal’s decision and said it was studying the judgment carefully to see if there were any grounds for appeal.

Analysts agreed the news would boost BAA chief executive Colin Matthews. BAA, which is owned by Spanish firm Ferrovial, will now have longer to dispose of other sites, meaning it will be able to sell them in improved economic conditions.