Acushnet said it will appeal the ruling, and has converted production of the golf balls so that they are outside the patents in question.

Callaway said late Monday that the U.S. District Court in Wilmington, Delaware, has granted the company's request for a permanent injunction on sales of Acushnet's current line of the Titleist Pro V1 balls, effective no later than Jan. 1. At Callaway's request, professional golfers will be allowed to use the balls through the end of this year.

The court also rejected a request from Acushnet to overturn a jury's December 2007 ruling in favor of Callaway in the patent dispute.

"We strongly disagree with the judge's ruling, and will file an appeal and seek relief from the injunction," Joe Nauman, an executive vice president with Acushnet, said in a news release late Monday.

Nauman said the ruling "will not have any impact on our ability to supply our customers with Pro V1 golf balls," because Acushnet in September converted production of existing Pro V1 models "so that they are outside of the patents in question."

He also said Acushnet plans to introduce new Titleist Pro V1 products early next year "that are also outside the scope of the patents in question."

Acushnet said it does not expect the ruling to have a "material adverse impact" on its financial results.

Callaway sued in June 2007 over the Titleist Pro V1 line of golf balls, introduced in 2000. Callaway argued its patents involve technological breakthroughs in producing multilayer, solid core balls that the company argued resulted "in performance that had previously eluded the industry" and revolutionized the game.

Acushnet argued that the Titleist Pro V1 is based on more than 70 of its own patents.

Callaway shares slipped 6 cents to $9.95 in morning trading Tuesday. Shares of Acushnet's owner, Fortune Brands Inc., fell 92 cents, or 2.5%, to $36.37.