Ownership disputes arise where the assignment agreement is missing, ambiguous, or broader than the law permits.

Default rules. Copyright in works within the scope of employment belongs to the employer. Patentable inventions belong to the inventor absent assignment, subject to a shop right where the employer’s time and resources were used.

Present assignment language. A promise to assign creates an equitable obligation that can be defeated by a later actual assignment to a third party. Language that assigns presently — hereby assigns — transfers automatically as inventions arise.

Statutory limits. Several states void provisions purporting to assign inventions developed entirely on the employee’s own time without the employer’s equipment, supplies, facilities or trade secrets, and unrelated to the employer’s business or to the employee’s work. Agreements in those states must include the statutory notice.

Prior inventions schedules completed at hire, which resolve later disputes about what the employee brought.

Holdover clauses claiming inventions conceived within a period after departure, enforced only where limited to inventions resulting from work performed during employment.

Contractors. No default employer ownership. A signed present assignment is required, and its absence is the most common intellectual property diligence finding.