The deal, which values Heathrow at £4.5 billion, is the fourth time Ferrovial has trimmed its holding in the airports group in two years and reduces its stake to 25pc, down from 62pc when it bought BAA in 2006 in a £10.3 billion deal.
BAA, which changed its name to Heathrow Airport Holdings (HAH) last year, has changed dramatically since the 2006 takeover, as the UK’s competition authorities have forced the company to sell off Edinburgh, Gatwick and Stansted airports. Heathrow still owns Aberdeen, Glasgow and Southampton airports.
Ferrovial will remain the largest shareholder in Heathrow following the deal with USS, which is expected to complete on Thursday.
USS will hold the seventh biggest stake behind China Investment Corporation, the sovereign wealth fund which bought 10pc of the airports operator in October 2012.
“This sale of a stake in HAH is a further part of Ferrovial’s investment diversification strategy. Following this deal, we reiterate our role in HAH as the main shareholder and industrial partner in the long term,” Mr Meirás said.
Ferrovial is selling the stake in FGP Topco, the holding company for Heathrow.
USS is the final salary pension scheme for universities and other higher education institutions in the UK. It manages around £40 billion, making it one of the largest pension schemes in the UK.
In October 2011, Ferrovial sold a 5.88 per cent stake to Alinda Capital Partners for €325m. Less than a year later, in August 2012, it struck a deal with Qatar Holdings before further reducing its holding to 33.65 pc last October through an agreement with China Investment Corporation.
The latest deal with USS comes amid a row with airlines and the UK’s airports regulator over the maximum return Heathrow’s shareholders should be allowed to generate on their investments.