Answer ... A US patent grants the holder the right to exclude anyone from making, selling, using, offering for sale or importing into the United States the patented invention (35 USC § 261). A US patent is considered the personal property of the patent holder and a patentee may therefore separately license any of the exclusionary rights of its patents to another party (35 USC § 261). A patent licence is essentially a permission, memorialised by a contractual promise not to sue, to perform acts that would be considered acts of infringement in the absence of the licence.
Patent licences can be exclusive or non-exclusive. An exclusive licence grants a licence to a party regarding one or more specific exclusionary rights of the patent and promises not to grant any further licences to third parties regarding those rights. A non-exclusive licence grants the licensee a right to make, use, sell or offer to sell the patented invention, but reserves the licensor’s right to practise the invention and to grant any other licensee the right to perform any of those activities.
Answer ... A patent owner can impose a number of limitations on a licence. For example, a patent owner can offer an exclusive licence or a non-exclusive licence. Under an exclusive licence, the licensor grants a party one or more specific exclusionary rights of the patent, and promises not to grant any further licences to third parties regarding those rights. Under a non-exclusive licence, the licensor grants the holder a right to make, use, sell or offer to sell the patented invention, but reserves its right to practise the invention and to grant any other licensee the right to perform any of those activities. If a patentee grants an exclusive licence to another without reserving for itself the right to practise the invention, it can be found liable to the licensee for patent infringement (US Valves, Inc v Dray, 212 F3d 1368, 1373-75 (Fed Cir 2000)). Patent owners can also restrict the licensee’s right to sub-license the patent to a third party.
Patentees may also use ‘field of use’ provisions, which grant rights limited to specific uses of the patented technology but withhold permissions to use the patent technology for other uses (Monsanto Co v Scruggs, 459 F3d 1328, 1338 (Fed Cir 2006)). Patent licences may also be limited to a territory or to a period less than the life of the patent.