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This research examines United States and Japanese laws regarding patent rights in collaborative inventions, and inquires whether these laws may impede technology transfers by creating uncertainty regarding the ownership, validity, or enforceability of the resulting patents, or by imposing undue obstacles to the licensing or assignment of such patents. Where the laws of the two countries differ, this paper compares the merits of each approach and also assesses whether the differing approaches could be troublesome for cross-border transactions.

One of the most significant differences between United States and Japanese law regarding joint inventions is in the requirement of consent for certain activities involving a jointly owned patent. In Japan, unlike the United States, all joint owners of a patent must consent to a non-exclusive license of the patent, or to the transfer of a single joint owner’s share, while in the United States, unlike Japan, a jointly owned patent cannot be enforced through an infringement action without the consent of all joint owners. Thus, while the consent requirements differ in the two countries, in each case they can present obstacles to the full enjoyment of a joint owner’s share of the patent.

In both countries, the definition of joint inventorship is imprecise, and even honest mistakes in identifying which persons qualify as joint inventors can lead to invalidation. In the United States, such errors can often be corrected without invalidating the patent, but in Japan, no such correction mechanism exists.

Finally, in light of recent Japanese court decisions on the subject of remuneration for employee inventions, employer allocations of remuneration in the future will need to carefully identify and quantify the respective contributions of all joint inventors. Such precision is generally not required in the United States.

Publication Citation

2005 IIP Bull. 86.