First Interstate Bancorp, some analysts are worrying Washington Mutual Inc. will stumble next.

Despite its success with 21 previous mergers, there's concern that the Seattle thrift's latest and largest acquisition - $43 billion-asset Great Western Financial, Chatsworth, Calif. - may go awry.

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.