Linear: Appeals court upholds patent ruling

Linear Technology Corp. said Friday that the Federal Circuit Court of Appeals ruled in line with an earlier decision that found Linear's claims that Advanced Analogic Technologies Inc. infringed on one of its patents were invalid.

Linear, which makes chips that convert analog signals into digital ones for use in electronic devices, said the U.S. International Trade Commission administrative law judge had previously found that another Linear patent was valid and infringed on by some Advanced Analogic products.

Linear shares fell 63 cents to $32.63, while Advanced Analogic shares fell 3 cents to $4.58.