STORY: Shares of First Republic slid 25% in early trading on Friday after being briefly halted as $30 billion in deposits injected by large U.S. banks, including Morgan Stanley and JPMorgan Chase, failed to quell investor worries about the beleaguered lender.

"What has happened is that the $30 billion injection is just an injection," Rathbun said. "It has not actually added any equity to the banking balance sheet. So what the investors are afraid of is it is not a long-term solution, and equities are actually a long-term instrument. And so when the markets look far out, they're thinking 'what next?'"