LITTON SAYS THAT IT will "almost certainly" appeal against the surprise decision of a US federal judge to nullify a $1.2 billion patent infringement which it was awarded in a 1993 patent lawsuit against Honeywell.

Honeywell vice-president Edward Grayson says that the group is "delighted" with the decision, which nullified the 1993 verdict by invalidating a Litton patent which covers a process to coat mirrors used in ring-laser gyroscopes (RLGs).

The court found that Litton's patent was unenforceable, since the innovation was an "obvious" combination of two existing processes and that Litton had also failed to disclose certain information when applying for the patent.

Litton president and chief executive John Leonis says that his company is "disappointed" with the judgement and that he "...anticipates filing an appeal".

The court action stems from March 1990, when Litton filed a lawsuit against Honeywell alleging infringement of a re-issued 1989 patent covering the RLG mirror-coating system.

Honeywell retaliated in December 1990 by filing counterclaims against Litton, alleging that its competitor had attempted to monopolise the inertial-reference-system market and had interfered with Honeywell's relationships with suppliers. This competition case is scheduled to be heard in November.

Honeywell, which invented the RLG in the 1960s and has some 55% of the commercial market, has strongly contested any patent infringement.

The RLGs consist of a triangular block of glass, with a cavity containing two counter-rotating laser beams which sense rotation of the gyro. Three RLGs are incorporated into a system which stabilises and navigates an aircraft by sensing motion in pitch, yaw and roll.

Source: Flight International