The businessmen who bought 10% of Anglo Irish Bank last summer, using funds supplied by the bank, include the co-owner of the K Club and the builder behind the Dundrum Shopping Centre. The “golden circle” also includes the country’s biggest housebuilder and the founder of a private hospital group.

Four of the 10-strong group of investors assembled by David Drumm, Anglo Irish’s former chief executive, are: Gerry Gannon, Joe O’Reilly, Seamus Ross and Jerry Conlan. Either they or some of their companies now owe several billion to Anglo. All four declined to comment last week.

Gannon co-owns the K Club, which hosted the 2006 Ryder Cup, with Michael Smurfit. He is the founder of Gannon Homes and owns a large amount of land in north and south Dublin.

O’Reilly is best known for developing the €1 billion Dundrum Shopping Centre. His company, Castlethorn, plans to build a €1.2 billion new town in Adamstown, west Dublin. He also plans a mixed-use development on O’Connell Street in Dublin.

Longford-born Ross runs Menolly Homes, the country’s biggest housebuilder. He owns Dunboyne Castle in Co Meath and recently ended a dispute over profits made on the development of houses in the K Club. He lost millions when the International Securities Trading Corporation (ISTC), a finance company set up by Tiernan O’Mahony, a former Anglo executive, came close to collapsing.

Conlan is the least well-known of the four. He sold 400 acres of land he co-owned in Naas, Co Kildare, known as Millennium Park, for €340m. He used much of the proceeds to found the Mount Carmel Medical Group which owns a maternity hospital in Rathfarnham, south Dublin. Mount Carmel has been appointed by the Health Service Executive to build private hospitals on the grounds of public hospitals as part of the co-location strategy.

The Sunday Times has been able to ascertain that the following businessmen, some of whom have had dealings with Anglo, are not among the 10 investors: Sean Mulryan, Patrick Doherty, Sean Dunne, Derek Quinlan, Denis O’Brien, JP McManus, John Magnier, Noel Smyth, Michael Whelan, Jim Mansfield, Richard Barrett, Johnny Ronan and Fintan Drury.

Patrick Kearney, a founder of PBN Property in Belfast, did not return repeated calls made last week. He was variously “in a meeting”, “in another meeting” and then “flying to Gibraltar”. Kearney is Anglo’s largest client in Northern Ireland and a close friend of Drumm. His business partner, Neil Adair, established Anglo’s Belfast branch.

John McCabe, the founder of McCabe Builders, also refused to comment last week. He was said to be “out of the office”, then “not at home” and finally The Sunday Times was told “he will call you back if he wants to”.

McCabe is an important Anglo client who lives on a stud farm in Meath formerly owned by Charles Haughey, the late taoiseach.

Last week Ulick McEvaddy, a well-known business figure, described the “Anglo 10” as “heroes” who were prepared to put themselves at risk to support the bank.

One banking source said: “Sure, they were patriotic, but if your bank asks you for a favour [in these market conditions] you do it.”

In total, Anglo Irish Bank lent €451m to a group it has described as “10 long-standing clients”, to buy 10% of the bank. The shares are believed to have been acquired through nominee companies.

The transaction was agreed to prevent the stake acquired through contracts for difference (CFDs) by businessman Sean Quinn coming to the market last summer. It was feared that this would result in a sharp fall in Anglo’s share price.

Three-quarters of the loans were secured against the shares themselves, with the remaining 25% secured on the participants’ “personal assets”.

The bank admits it is likely to have to write off €300m of the money it loaned the 10 investors. Because Anglo has since been nationalised, this loss now passes to the Irish taxpayer.

The Financial Regulator has “categorically” denied knowing the terms of the deal or the identity of the investors beforehand.

It said it knew “steps” to unwind the Quinn shareholding were being put in place, but has not explained why it did not seek further information on the final structure of the deal.

The emergence of four of the 10 names will put further pressure on the government to disclose the others.

Brian Cowen, the taoiseach, said last week that his advice from the attorney general was that he could not disclose the names.

Donal O’Connor, the Anglo chairman, said last week it “would be wrong for the bank to refer to any transactions or dealings with any specific customer of the bank”.

Eamon Gilmore, the Labour party leader, yesterday called on the government to appoint a High Court inspector to investigate various activities at Anglo.

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