Mass. regulator subpoenas UBS, Merrill, BofA

BOSTON (Reuters) - Massachusetts' top securities regulator said on Friday that his office is demanding information from three large investment houses as he deepens a probe into the $330 billion auction-rate securities market.

William Galvin, the state's secretary of the Commonwealth, issued subpoenas to UBS Securities (UBSN.VX), Merrill Lynch MER.N and Bank of America Investment Services (BAC.N) to determine whether they told investors about the potential risks of these investments.

Last month Galvin asked nine prominent investment managers for help in seeing how their clients reacted as the auction-rate securities market became the latest victim of the credit market crunch.

(Reporting by Svea Herbst-Bayliss)