Patent eligibility should hinge on an invention’s usefulness and the whole claimed technology rather than individual claims, according to draft text of a potential bill unveiled by House and Senate lawmakers.

Any useful process, machine, manufacture, or composition of matter, or a useful improvement of an invention would be patentable under the draft text issued by a group of lawmakers, including Sens. Thom Tillis (R-N.C.) and Chris Coons (D-Del.) The text would introduce the definition of “useful” into the Patent Act.

The lawmakers’ effort comes in response to complaints by practitioners and companies that U.S. Supreme Court decisions on patent...