Four of the five names on the Irish bank test list are well known retail banks, but the fifth name - Merrill Lynch International Bank Ltd -  is less well known.

Merrill Lynch International Bank is a subsidiary of Bank of America/Merrill Lynch, which was formed by the takeover of Merrill by BofA in september 2008.

Based in Leopardstown, Dublin 18, it declared a loss in 2012 of $729 million.  Its balance sheet was $490 billion.

Its 2012 annnual report says:

"The Group is a banking entity and has its head office in Ireland with branch offices in Amsterdam, Bahrain,
Frankfurt, London, Madrid, Milan, Rome, Singapore, Toronto and Paris.

The Group acts as a principal for debt derivative and foreign exchange transactions and engages in advisory, lending, loan trading and institutional sales activity. The Group also provides collateralised lending, letters of credit, guarantees and foreign exchange services to, and accepts deposits from, its clients.

The Group provides mortgage lending, administration and servicing in the UK non-conforming residential
mortgage market. The Group's activities are regulated by the Central Bank of Ireland."

However the Central Bank of Ireland points out that Merrill Lynch International Bank's home country regulator is in the US, where its parent company (BofAML) is based.

It is the same with Ulster Bank, which is a subsidiary of British regulated bank RBS.  It has been the British taxpayer who has been paying for Ulster Bank's losses in Ireland, and it would be expected that were MLIB to run into difficulties, the Irish taxpayer would not be on the hook.