By James Fox of Arnold & Porter LLP
Patents have the attributes of personal property, and are assignable by an instrument in writing (35 U.S.C. § 261). Two recent cases illustrate how important the language used in an employment contract can be in determining when, and if, ownership passes from an inventor to an employer. A recent United Kingdom case highlights how, for European patents at least, rights to patent ownership may be separate from rights to priority, and that the time at which ownership passes from an inventor to an employer determines priority and can be critical to patent rights.
Typically, the inventor owns an invention unless and until ownership passes to another. Ownership of an invention passes when an assignment is executed. However, under Federal law, which governs U.S. patent assignments, where an employment agreement expressly grants the employer rights in future inventions, once an invention comes into being, no further act is required and transfer of title occurs by operation of law (DDB Technologies, L.L.C. v. MLB Advanced Media, L.P. 517 F.3d 1284, 1290, citing Filmtec Corporation v. Allied Signal, Inc. 939 F.2d 1568,1573 (1991)). Thus, the time at which an employer gains ownership of a patent may depend on the employment agreement or on the timing of the execution of an assignment document.
A recent case in the United Kingdom demonstrates, for some foreign patents, at least, that the time an employer ...