A Canadian pension plan manager is leading the race to buy a half-share in a swath of warehouses and offices around Heathrow for about £600 million from BAA, the airports operator.

Caisse de Dépôt et Placement du Québec was part of the consortium, led by Ferrovial, the Spanish construction giant, that bought BAA for £16.3 billion last year.

Ferrovial’s London investment bankers at Morgan Stanley have issued a sales prospectus for the half-share in BAA’s Airport Property Partnership to an array of potential suitors, but La Caisse is a significant step ahead of rivals because it has arranged for a right of first refusal to match any offers.

Potential bidders, discovering that La Caisse has a “put” option over the half-share, have been thrown into confusion over how they should price their first-round bids, which are due on July 20, sources told The Times. The sale process makes for an “uneconomic auction”, according to some sources, because La Caisse can wait for two weeks to view all the bids before deciding whether to match the highest offer.

Should La Caisse not bid and second-round offers come in lower than the first-round bids, La Caisse must be offered the assets at the lower price, under rights of first refusal that it has secured from Ferrovial.

The sale may drag on until September before a preferred bidder is chosen, delaying deal completion possibly until Christmas, sources said.

The deal includes a sale of BAA Lynton, BAA’s wholly owned property development unit headed by John O’Halloran. It would be the largest sale of industrial property in Britain for more than a year. The combined value of the partnership fund and BAA Lynton is thought to have risen from about £1 billion before Christmas to nearly £1.2 billion. The fund carries about £400 million of debt.

The jewel in the crown is the BA cargo centre at Heathrow, covering 400,000 sq ft and possibly worth £250 million. In total, the Airport Property Partnership owns about 35 properties wrapped in a Jersey-based property unit trust.

Segro, the FTSE 100 developer formerly known as Slough Estates and Britain’s largest warehouse developer, has already confirmed its interest in the deal. Segro is sitting on a cash windfall after securing a deal last month to sell its American holdings.

Other potential bidders include Morley, the asset manager for the British insurer Aviva. Morley owns the other half of the Airport Property Partnership with BAA. Goodman, the industrial property landlord previously known as Macquarie Goodman, is another likely bidder. In April Goodman bought Rosemound for £336 million. Other potential suitors include Brixton Estate, the industrial developer, and ING Real Estate.

La Caisse has been building its portfolio in Europe. It was part of a consortium, led by Hochtief Airport, of Germany, which in May bought a 75 per cent stake in Budapest airport from BAA for €1.9 billion (£1.2 billion).

Rents and capital values for industrial warehousing around Heathrow have surged over the past six months as investors chase a limited stock of prime industrial space around the airport.

High-flyer

Caisse de Dépôt et Placement du Québec, known as La Caisse, was founded in 1965 to manage public pension funds and now has $185 billion in assets under management. Its holdings include the Ritz Plaza in New York

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