Question 1

Which states limit what an employee invention-assignment agreement can cover?

Accepted Answer

A group of states — led by California (Lab. Code § 2870) and including Washington, Illinois, Minnesota, North Carolina, and others — void by statute any clause that assigns an invention an employee developed entirely on their own time, without employer resources, and unrelated to the employer’s business. States without such a statute apply common-law default rules. See the comparison table for each jurisdiction.

Question 2

Who owns an employee’s invention if there is no written assignment?

Accepted Answer

As a default rule the employee-inventor owns the invention (Stanford v. Roche), with two common exceptions: the employer owns it if the employee was specifically hired to invent it, and the employer may hold a non-exclusive "shop right" to use an invention made with employer resources. A written assignment agreement is what changes this default — within the limits each state imposes.

Jurisdiction	Own-time invention carve-out?	Bottom line	Main law or case	Last reviewed	Details
California	Statutory carve-out	A California employer may require assignment of inventions tied to its business or to the employee's work, but Section 2870 voids forced assignment of true own-time, own-resource inventions, the employer must give written notice under Section 2872, and overbroad holdover clauses are void under Section 16600.	Cal. Lab. Code §§ 2870–2872; Cal. Bus. & Prof. Code § 16600	Jun 29, 2026
Employee notice required? Yes Who owns by default? Employee (absent assignment) Trailing-clause limit Limited by statute Carve-out scope An invention the employee developed entirely on their own time, without the employer's equipment, supplies, facilities, or trade secrets, that neither relates to the employer's business or anticipated R&D nor results from the employee's work Future effective law —

Employee Invention-Assignment Laws by State