BAA will not be granted leave to appeal against a Competition Commission decision forcing it to sell Stansted and one of either Edinburgh or Glasgow Airports.
BAA presently operates six airports in the UK, with London Heathrow, Southampton Airport and Aberdeen Airport also under its control.
However, a Competition Commission investigation in 2008 raised concerns the dominant position of the operator was stifling the competitiveness in the UK aviation sector.
BAA was subsequently forced to dispose of Gatwick Airport, with further sales now seemingly inevitable.
A BAA spokesperson said: “We are disappointed by the Supreme Court’s decision not to hear our appeal.
“We continue to make the case to the Competition Commission that the circumstances in which they found reason to force the sale of airports have changed significantly since early 2009 and should certainly be reviewed in the light of the Government’s policy to rule out new runway capacity in the South East of England.”
BAA first appealed to the Competition Appeal Tribunal (CAT) in late 2009 in order to prevent the sale of Stansted and one of either Edinburgh or Glasgow Airports.
The complaint was upheld, with the Competition Commission successfully appealing to the Court of Appeal, which in October 2010 overturned the CAT decision, upholding two of the five grounds argued by the Competition Commission.
In November 2010, BAA sought permission from the Supreme Court to appeal the Court of Appeal decision.
BAA has today been informed that this permission has not been granted.
BAA sold Gatwick Airport to Global Infrastructure Partners (GIP) – a fund backed by Credit Suisse and General Electric, which also operates London City Airport – for £1.51 billion in 2009.
The Competition Commission earlier welcomed the Supreme Court decision.
Peter Freeman, chairman of the CC said: “We are pleased that the Supreme Court has made this decision.
“Since November we have been considering whether there has been any change in circumstances following the completion of the BAA investigation in March 2009, which should cause us to reconsider implementing the original decision.
“The Supreme Court’s decision means we can press ahead with this process and hopefully bring it to a swift conclusion in the interests of the travelling public.”
The commission has been consulting with all interested parties on whether there has been any change in circumstances and expects to issue its provisional decision on the matter later next month.