NEW YORK ( TheStreet) -- Fifth Third Bancorp ( FITB) revealed that the Securities and Exchange Commission has subpoenaed the bank for information regarding commercial loans, according to the bank's 10K filing issued Monday.

The 10-K says the SEC is investigating the controls and procedures of the bank's commercial loans that "may result in one or more such material adverse consequences," such as fines.

News of the inquiry have hit Fifth Third's shares hard with the stock down 4.5%, to $13.92, in premarket trading.

This is the third time the SEC has requested information about the bank's commercial loan portfolio, a Fifth Third spokesperson said. The first request for information was in November. The spokesperson could not provide any more details about the investigation.

Stifel analysts Christopher Mutascio and Brian Zabora believe said in a note they expect the investigation to affect the share price.

"We continue to like names like PNC Financial ( PNC) over FITB. Since the beginning of the year, the shares of PNC are up 1.8% and the shares of FITB are down 0.9%... We think the spread between the two stocks could widen on the SEC's investigation of FITB," wrote the analysts in a note.

Although Fifth Third has been rumored to be a target, the investigation by the SEC is unlikely to prompt a sale, according to analysts. "We believe the FITB management team is much more of a long-term buyer than it is a near-term seller," said Mutascio.

The analysts said that the subpoena could be similar to the issued to CVB Financial ( CVBF) in July 2010 and has not yet been resolved.

Robert W. Baird analyst David George agrees. "Any speculation that it could prompt a sale is premature," he said in a phone interview.

If Fifth Third were to sell, it would most likely sell for a lower premium than recent the acquisitions such as Comercia's ( CMA) $1 billion purchase of Sterling Banshares ( SBIB) or Bank of Montreal's ( BMO) $4.1 billion buyout of Marshall & Ilsley ( MI).

"The reason being is that the potential acquirers for banks as large as FITB are of similar size as the takeout candidates. Thus, they cannot easily absorb the significant purchase accounting loan marks on the acquired institution," Mutascio said.

--Written by Maria Woehr in New York.

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