Adds details from the WSJ report, background in bullets

July 6 (Reuters) - U.S. banks, including JPMorgan JPM.N and Bank of America BAC.N, have in recent months held early talks about a deal to buy a network owned by the payments firm Fiserv FISV.O that could allow them to bypass federal debit-card fee caps, the Wall Street Journal reported on Monday, citing sources.

• The cap banks are reported to be looking to sidestep traces back to the 2010 Durbin Amendment, which limits the fees large banks can collect from merchants on debit-card transactions when routed through an outside network. However, banks would be exempt from that cap if they also own the network, the WSJ report said.

• Other banks that have held preliminary and tentative discussions include Wells Fargo WFC.N and PNC Financial Services Group PNC.N, the report added.

• The report sent Fiserv's shares up 4.3% in after-hours trading.

• Several of the companies that looked at the Fiserv network have already decided it would be unlikely for them to move forward, as they expressed concern that such a deal could prompt backlash from lawmakers, regulators and merchants, the report added.

• JPMorgan declined to comment, while Fiserv, BofA, Wells Fargo and PNC Financial did not immediately respond to Reuters' requests for comment outside regular business hours.