New York investment bank Sandler O'Neill is advising US private equity firms JC Flowers and the Carlyle Group in the consortium which is interested in investing one or a number of Irish banks.
The bank, which was founded in 1988 by senior executives from several Wall Street firms, runs an investment advisory business and has consulted on 21 takeovers and mergers in the US banking sector this year.
In 2007, Sandler O'Neill was involved in 62 transactions in the financial services industry valued at $50.8 billion (€40 billion). The deals ranged in size from $5.5 million to $25 billion.
In the biggest deal this year, it advised the world's largest futures exchange, CME Group, on its purchase of Nymex Holdings, owner of the New York Mercantile Exchange, in a $7.6 billion transaction.
Sandler O'Neill employs more than 250 staff. It has offices in Boston, Chicago, San Francisco and Atlanta and a mortgage finance business in Memphis.
The Carlyle Group, based in Washington DC, is one of the largest private equity firms in the world. It has more than $91 billion (€72.6 billion) under management and 64 investment funds in four areas - buy-outs, growth capital, real estate and leveraged finance.
Since its foundation in 1987, the firm has invested $52.7 billion in 870 transactions. It invests for more than 1,300 investors from 67 countries using 535 investment advisers. It had committed $3.5 billion of its own capital to funds.
Carlyle has not been immune from the credit crunch.
One of its affiliates, Carlyle Capital Corp, a $22 billion mortgage-backed securities fund, went bankrupt in March after it could not meet margin calls from its lenders.
Prominent political figures, including former US president George HW Bush and former British prime minister John Major, have held senior positions in the Carlyle Group.
US private equity firm JC Flowers, which has a track record of investing in distressed banks, is with the Carlyle Group providing the financial muscle in the consortium that has shown an interest in investing in the Irish banks and is in contact with the Government.
The company was founded in 2001 by billionaire Christopher Flowers, a former executive at investment bank Goldman Sachs. Dominic Silvester, who was educated at Blackrock College, Dublin, is chief executive of insurer Enstar, where JC Flowers is the largest shareholder.
JC Flowers failed in a bid for British bank Northern Rock last year before it was nationalised. It was also interested in US investment bank Bear Stearns. Together with Icelandic bank Kaupthing, it had looked at a possible bid for Irish Nationwide Building Society last year.
JC Flowers is a shareholder in beleaguered German lender Hypo Real Estate which bought Dublin bank Depfa last year.
Cardinal Asset Management has assembled the various private equity companies into the exotically named Maulabracka consortium, described as "a fund of funds", that wants to buy into one or more Irish banks.
Cardinal is not the only Irish firm advising the consortium.
Bryan Turley, chief executive of Sorrento Asset Management, is working with the group and another Dublin company is also believed to be advising the grouping of investment giants.
Established by Nick Corcoran and Nigel McDermott, Cardinal was the first independent Irish hedge fund to receive institutional support when global fund management company FC bought a stake.
Mr Corcoran previously worked at AIB Capital Markets before moving to International Investments Underwriting (IIU), the investment holding firm owned by financier Dermot Desmond, and later to Zurich Capital Markets.