A top policy analyst warned Thursday that recently proposed megamergers are likely to flop because they are based on unrealistic assumptions.

"You really have to wonder how well these consolidated institutions can do for shareholders," said Karen Shaw Petrou, president of the consulting firm ISD-Shaw Inc. and a former BankAmerica Corp. vice president.

Subscribe Now

Access to authoritative analysis and perspective and our data-driven report series.

14-Day Free Trial

No credit card required. Complete access to articles, breaking news and industry data.