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,
Shabbat lamp Shabbat lamp A Shabbat lamp is a special lamp that has movable parts to expose or block out its light so it can be turned "on" or "off" while its power physically remains on. This enables the lamp to be used by Shabbat observant Jews to make a room dark or light during Shabbat without actually switching the electrical power on or off, an act that is prohibited during Shabbat. One company manufacturing such lamps is Kosher Innovations, a Toronto-based company, based on a US patent application registered to Shmuel Veffer in 2004. Tens of thousands of units have been