NEW YORK (Reuters) - Investors have reached $96 million in settlements with the final five defendants in private U.S. litigation accusing banks of rigging a key interest rate benchmark in the global derivatives market, boosting the total payout to more than $500 million.

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BNP Paribas SA BNPP.PA and Morgan Stanley MS.N will each pay $33.5 million, Nomura Holdings Inc 8604.T and Wells Fargo & Co WFC.N will each pay $8.75 million, and brokerage ICAP Capital Markets LLC will pay $11.5 million, according to filings on Friday night in U.S. District Court in Manhattan.

Upon receiving court approval, the settlements would increase the total recovered from 14 banks plus ICAP to $504.5 million. The defendants denied wrongdoing in agreeing to the preliminary settlements.

Several pension funds and municipalities had accused banks of conspiring to manipulate the benchmark known as ISDAfix for their own gain from at least 2009 to 2012, distorting part of the $532 trillion global derivatives market.

Companies and investors use ISDAfix to price swaps transactions, commercial real estate mortgages and structured debt securities.

Daniel Brockett, a lawyer for the plaintiffs, in a court filing said only about 12 antitrust class actions had approved settlements topping $500 million, assuming the latest accords are approved.

Goldman Sachs Group Inc's GS.N $56.5 million payout was the largest in the ISDAfix case.

Several banks have settled similar allegations by the U.S. Commodity Futures Trading Commission, including JPMorgan Chase & Co JPM.N accepting a $65 million fine on June 18.

The private litigation is among many lawsuits in the federal court in Manhattan accusing banks of conspiring to rig rate benchmarks, securities prices and commodities prices.

The case is Alaska Electrical Pension Fund et al v Bank of America NA et al, U.S. District Court, Southern District of New York, No. 14-07126.