A summary of Southern California-related business litigation developments during the past week.

Engine Cleaner Inventors Sue Automotive Firm: Two holders of a patent for an internal combustion engine scrubber sued Parker Automotive Corp. of Costa Mesa on grounds that Parker obtained a patent on a similar product after receiving an exclusive license to make their scrubber. In their federal lawsuit, Maurice Carmichael and Janis Binatena asserted that in 1987 they gave Parker the right to manufacture and sell the scrubber in return for royalties--which were never paid. A condition of the agreement was that all modifications on the scrubber would be the property of the patent holders, the suit says. (Case No. 90-4920. Filed Sept. 13, 1990)