UPDATE 3-Big banks win dismissal of U.S. Treasury rigging litigation

(Adds comment from plaintiffs' lawyer, details)

By Jonathan Stempel

NEW YORK, March 31 (Reuters) - A U.S. judge on Wednesday
dismissed long-running litigation accusing 10 large banks of
conspiring to suppress competition in the now $21.2 trillion
market for U.S. Treasury securities.

U.S. District Judge Paul Gardephe in Manhattan ruled against
21 pension, retirement and benefit funds, as well as unions,
banks, individuals, and companies that traded in Treasuries, in
the proposed antitrust class action.

The defendants included Bank of America, Barclays
, BNP Paribas, Citigroup, Credit Suisse
, Goldman Sachs, JPMorgan Chase, Morgan
Stanley, NatWest Group and UBS, as well
as trading platform operator Tradeweb Markets.

Traders said the 10 banks, which from 2010 to 2014 handled
an estimated 75% of Treasury trades through the Federal Reserve
Bank of New York, used chat rooms to swap confidential customer
orders and coordinate strategies, to profit at clients' expense.

They said seven of the banks also conspired to boycott
electronic trading platforms that offered "anonymous" trading
and better prices for clients.

Manipulation allegedly occurred in the "when-issued" market,
or the period between when auction dates are announced and
securities are delivered.

But in a 53-page decision, Gardephe found no plausible
direct evidence of an antitrust conspiracy, and said the
plaintiffs' statistical analyses were "no substitute" for
evidence of individual or collective wrongdoing.

"Plaintiffs' statistical analyses are at most a 'plus
factor,'" he wrote. "But plus factors alone are not sufficient;
a plaintiff must also adequately allege parallel conduct. That
Plaintiffs have not done."

The claims date as far back as 2007. Gardephe gave the
plaintiffs until April 30 to amend their complaint.

One of the plaintiffs' lawyers, Dan Brockett from Quinn
Emanuel Urquhart & Sullivan, said they "will consider all
options to protect the interests of the class."

The litigation began in July 2015, shortly after news
reports that the U.S. Department of Justice was probing possible
Treasury manipulation by banks.

Earlier probes into manipulation of the Libor interest rate
benchmark and foreign currencies resulted in billions of dollars
in criminal and civil penalties for banks worldwide.

The case is In re: Treasuries Securities Auction Antitrust
Litigation, U.S. District Court, Southern District of New York,
No. 15-md-02673.
(Reporting by Jonathan Stempel in New York; Editing by Chris
Reese, Alexandra Hudson, Diane Craft and Jonathan Oatis)