[ by Howard Haykin ] The buzz on Wall Street got so loud that FINRA Chairman Rick Ketchum came down from his office to add his 2¢ - which was to announce that FINRA review allegations that Morgan Stanley have made inappropriate disclosures just prior to the IPO. On Tuesday, the FINRA Chairman specifically said regulators would "drill down and get to the truth" of the rumor that Morgan Stanley, Facebook's lead underwriter, shared negative news with a limited number of institutional investors before Facebook's initial public offering.  Ketchum added, "The allegations, if true, are a matter of regulatory concern" to FINRA and the SEC. [see C-I BTN story posted 5/22, "Morgan Stanley Cut Facebook Estimate..."] Some Things Better Left Unsaid. Morgan Stanley allegedly delivered some unexpected negative news to major clients in the run-up to Facebook's $16 billion IPO: The bank's consumer Internet analyst, Scott Devitt, was reducing his revenue forecasts for the company. It's unusual for analysts at lead underwriters to make such changes so close to the IPO - which is uncomfortably obvious - and it's unclear whether Morgan Stanley only told its top clients about the revised view or spread the word more broadly.  [C-I Note:  We never heard any such news.  Then again, nobody would ever accuse this company of being an institutional investor. For further details, go to:  [Reuters, via CNBC, 5/22/12].