UPDATE 5-UBS, U.S. settle tax evasion case

* Settlement may involve disclosure of thousands of names

* U.S. had sought names of 52,000 wealthy American clients

* Final form of agreement not yet in place

* Other governments may follow U.S. lead

* UBS shares rise sharply (Recasts first paragraph, adds comment on potential global impact, updates shares)

By Pascal Fletcher and Lisa Jucca

MIAMI/ZURICH Aug 12 (Reuters) - The days of secret bank accounts are numbered for Americans after UBS (UBSN.VX) (UBS.N) and the U.S. and Swiss governments agreed to settle a dispute over whether the Swiss bank should be forced to disclose the names of 52,000 rich U.S. clients suspected of tax evasion.

Lawyers involved in the case said Wednesday's settlement could involve the disclosure to U.S. authorities of 3,000 to perhaps more than 10,000 names of American clients suspected of using offshore accounts to evade taxes.

While details weren't disclosed, the parties have initialed agreements that will "take a little time to be signed in final form," Department of Justice lawyer Stuart Gibson told U.S. District Court Judge Alan Gold during a brief conference call.

The case is expected to be dismissed once a final agreement is in place. UBS and the government had reached a settlement in principle on July 31.

The deal is also expected to put European tax dodgers on notice as other governments are encouraged to seek out hidden accounts.[ID:nL7307308]

U.S. authorities believe the 52,000 U.S.-based clients of UBS may be hiding nearly $15 billion of assets.

Washington's case against UBS, the world's second-largest wealth manager, had strained relations between the United States and Switzerland because it challenged the latter's jealously guarded bank secrecy laws.

UBS shares closed 3 percent higher in Switzerland and were up more than four percent in afternoon trading in New York.

"This is definitely good news for UBS," said Milan Patel, a tax lawyer at Withers LLP in Geneva.

"However, this may mean that UBS could face a new legal battle in Switzerland if the account holders claim UBS violated Swiss bank secrecy laws by disclosing their names," Patel added. "Thus, UBS may have ended the U.S. legal battle only to start the Swiss legal battle."