Rolls Royce files patent suit against United Technologies over fan blade design.

Rolls Royce files patent suit against UTC

RESTON, Va. — Jet engine maker Rolls-Royce said Thursday that it has filed a patent infringement lawsuit against United Technologies over the design of engine parts.

The amended complaint, filed in U.S. District Court for the Eastern District of Virginia, alleges that fan blades in a United Technologies geared turbofan engine infringe on a Rolls-Royce patent.

In a statement, Pratt & Whitney, the United Technologies engine making division, denied that it violated the Rolls-Royce patent. It said the lawsuit lacks merit and that it plans to “vigorously defend itself.”

Rolls-Royce also claims other United Technologies engines also violate its patent.

Rolls-Royce is seeking unspecified damages and injunctions. The British company says the case is expected to go before a jury in the first half of 2011.

According to Rolls-Royce, the case dates to the late 1990s, when the two companies tangled in the U.S. Patent Office. Rolls-Royce said United Technologies’ attempts to have its patent struck were unsuccessful.

United Technologies did not immediately return a request for comment.