Heinrich Goebel, a German inventor and mechanic, patented three inventions, including a sewing machine hemmer improvement, a Geissler system of vacuum pumps improvement and an electric incandescent lamp. The lamp patent was actually an improvement for existing bulbs, consisting of sockets to connect the carbon filament and conducting wires.
Goebel claimed that he invented practical incandescent electric light bulbs in the 1850s for personal use and did not apply for patent. The lack of a patent combined with his work for American Electric Light Company eventually led to lengthy patent infringement lawsuits brought by Edison Electric Light Company. There is still debate, in modern times, as to whether Goebel or Thomas Alva Edison invented the first light bulb.