Science and technology in the United States finish. For example, the British engineer Joseph Swan built an incandescent electric lamp in 1860, almost 20 years before Edison. But Edison's light bulbs lasted much longer than Swan's, and they could be turned on and off individually, while Swan's bulbs could be used only in a system where several lights were turned on or off at the same time. Edison followed up his improvement of the light bulb with the development of electrical generating systems. Within 30 years, his inventions had introduced electric lighting into millions of homes. Another landmark application of scientific ideas to practical uses was the
Opposition procedure before the European Patent Office (the decision instead maintaining the patent as granted or in an amended form) leaves the way open for revocation by the national court. The EPO decision does not create an estoppel precluding a subsequent challenge by an unsuccessful opponent at the national level (at least before the English courts). The validity of a European patent can be scrutinised both at the national level, before a national court, and at the international level, before the European Patent Office during opposition. The same is not true for infringement proceedings, upon which national courts exercise exclusive jurisdiction. Each party to the opposition proceedings