All claims rule is an outdated principle of patents law according to which a patent is invalid unless every inventor named in the patent made an inventive contribution to every claim in the patent. The 1984 amendment clearly repudiates the rule. Section 116 of the Patent Act now expressly provides that inventors may apply for a patent jointly even though each did not make a contribution to the subject matter of every claim.
The "all claims" rule requires that, in a joint patent, each inventor must contribute to the subject matter of each claim. [AMP, Inc. v. Fujitsu Microelectronics, 853 F. Supp. 808, 817 (M.D. Pa. 1994)]