NEW YORK (Reuters) - Barclays Plc won the dismissal on Wednesday of U.S. class-action litigation by investors who bought its stock just months before the 2008 global financial crisis, and accused it of concealing its exposure to risky debt and an inability to manage credit risks.

U.S. District Judge Paul Crotty in Manhattan said investors failed to show that Barclays and underwriters led by Citigroup Inc deceived them when the British bank sold $2.5 billion of American depositary shares in April 2008.

Though the shares lost 80 percent of their value by the following March, Crotty said much of that decline could have reflected fallout from the collapse of Lehman Brothers Holdings Inc, the bailout of U.S. insurer American International Group Inc, and government capital injections into other British banks.

“In such circumstances, the prospect that the plaintiff’s loss was caused by the alleged misrepresentations decreases,” Crotty wrote in a 51-page decision.

The decision could end 8-1/2 years of litigation, and remove one hurdle as Chief Executive Jes Staley focuses on scaling back Barclays’ geographic reach, increasing the bank’s emphasis on investment banking, and addressing various regulatory probes, including over the financial crisis.

Lawyers for the investors did not immediately respond to requests for comment. Barclays spokeswoman Kerrie Cohen declined to comment, as did Citigroup spokeswoman Danielle Romero-Apsilos.

The case is one of many accusing big banks of inflating their share prices by hiding or being too slow to fix souring credits on their balance sheets.

Barclays wrote off 2.8 billion pounds ($3.7 billion) on subprime mortgages and other risky debt a few months after the ADS offering, and a large capital-raising plan soon followed.

But Crotty said Barclays’ disclosures to investors about its capital strength and dealings with British financial regulators were sufficient, as were its disclosures about how further credit market “dislocations” might hurt its finances.

“Given these disclosures, a reasonable investor would infer how continued credit market dislocation might reasonably be expected to have a material impact on future revenues,” leaving Barclays “vulnerable to additional write-downs,” Crotty wrote.

The judge dismissed other parts of the lawsuit in 2011. A federal appeals court revived the portion about the $2.5 billion ADS offering two years later.

The case is In re: Barclays Bank Plc Securities Litigation, U.S. District Court, Southern District of New York, No. 09-01989.