TEHRAN Microsoft Corp.'s Ultimate TV-brand personal video recorder may infringe on a patent just issued to rival TiVo Inc., said an executive at that San Jose, Calif., company. The patent, announced yesterday after the markets closed, gives TiVo formal recognition for developing the personal video recorder, which lets TV viewers pause live programming and record shows onto a hard drive.

TiVo Chief Executive and Chairman Michael Ramsay said the company hopes to use the patent to expand its licensing efforts. He declined to elaborate on whether TiVo would take legal action against other players in the personal video recording field.

One of those is Microsoft, which in January introduced Ultimate TV. Replay TV of Mountain View also offered such a product until November.

Jim Barton, TiVo's chief technology officer, said the company doesn't know yet whether Ultimate TV infringes on its patent, which TiVo filed in July 1998.

"We're going to recommend (Microsoft) examine the patent and see if it does ... so we could work out a licensing deal," he said.

Microsoft said in a prepared statement: "As a matter of policy, Microsoft does not comment on the specific patents its competitors receive. However, Microsoft has an extensive portfolio of patents of its own that protects its products."

Ultimate TV is a combined product and service from Microsoft's Web TV Networks.