Thomas Edison of the Edison patent to charge a more reasonable rate for the use of the Edison patent rights and lowering the price of the electric lamp. On October 8, 1883, the US patent office ruled that Edison's patent was based on the work of William E. Sawyer and was, therefore, invalid. Litigation continued for nearly six years, until October 6, 1889, when a judge ruled that Edison's electric light improvement claim for "a filament of carbon of high resistance" was valid. To avoid a possible court battle with Joseph Swan, whose British patent had been awarded a year before Edison's,
Representation before the European Patent Office point when candidates failed to select the "right" starting document (for assessing the inventive step of some claims) and the blanket addition of 10 points to the grade of all C papers, was strongly criticized. As of November 2010, there were a little more than 10,000 persons on the list of professional representatives, "just less than 1500" "legal practitioners entitled to represent before the EPO", and "about 300 patent law firms, which are registered as „associations of representatives“ within the meaning of ". As of January 2013, there were precisely 10,427 professional representatives. Under , an association of professional representatives