Can an employment NDA legally claim ownership of personal side projects built on my own time?

Can your employer claim your side projects? Learn how IP assignment clauses work and how to protect your work. Use TermScore to analyze your contract today.

May 29, 2026TermScore Research707 words

Can an employment NDA legally claim ownership of personal side projects built on my own time?

In most jurisdictions, an employer cannot claim ownership of personal side projects developed entirely on your own time, using your own equipment, and unrelated to the employer's business. However, broad 'Invention Assignment' clauses can legally override these protections if you do not explicitly carve out your existing or future work.

Key takeaway: An NDA is often paired with an Invention Assignment Agreement. Never assume your side project is safe just because you built it at home; the legal language in your contract is the final authority.

Understanding Invention Assignment Clauses

Most employment contracts contain an 'Invention Assignment' clause. This clause dictates that any intellectual property (IP) you create during your employment belongs to the company. While this is standard for work related to your job duties, aggressive contracts often use 'catch-all' language that claims ownership of anything you create while employed.

The Three Pillars of Protection

To keep your side projects, you must generally satisfy three criteria. If you fail any of these, your employer may have a legal claim to your work:

  • No Company Resources: You did not use company laptops, software licenses, servers, or proprietary data.
  • No Company Time: The work was performed entirely outside of your contracted working hours.
  • No Business Relation: The project does not relate to the employer's actual or anticipated business, research, or development.

Action Item: Audit your current contract for the phrase 'related to the business of the company.' If this is defined broadly, your side project could be considered 'related' even if it is in a different niche.

Jurisdictional Protections

Several U.S. states have enacted laws that specifically protect employees from overreaching IP assignment clauses. These laws essentially state that any contract provision requiring an employee to assign rights to an invention developed on their own time is unenforceable if it meets the three pillars mentioned above.

StateKey Protection Statute
CaliforniaLabor Code Section 2870
WashingtonRCW 49.44.140
Illinois765 ILCS 1060/2
New JerseyN.J.S.A. 34:1B-265

Action Item: Check if your state has an 'Employee Invention Act.' If you live in a state without these protections, your contract language is the only thing standing between you and your employer's claim to your IP.

How to Legally Protect Your Side Projects

If you are currently negotiating an employment contract, you must be proactive. Do not rely on verbal assurances from HR or your manager; these are rarely enforceable in court.

  1. Create an 'Excluded Inventions' List: Attach an exhibit to your contract that lists all existing side projects you own. This creates a 'prior art' record that the company cannot claim.
  2. Use Separate Hardware: Never log into your side project repository from a work-issued laptop. Use a dedicated machine for personal development.
  3. Document Your Hours: Keep a log of when you work on your side projects to prove they were developed outside of company time.
  4. Request a Carve-Out: Ask for a clause that explicitly states: 'The Company acknowledges that the Employee may engage in independent projects that do not compete with the Company, and the Company waives any claim to such work.'

Key takeaway: If your employer refuses to sign an 'Excluded Inventions' list, consider this a major red flag. It suggests they intend to claim ownership of your future innovations.

The Risks of Ignoring Contractual Language

If you build a valuable product while under an overly broad contract, you risk a 'Cloud on Title.' This means that if you try to raise venture capital or sell your side project, investors will perform due diligence, find your employment contract, and refuse to fund you because your employer could legally sue for ownership. This can effectively kill your startup before it begins.

Action Item: If you have already built a project, consult with an IP attorney to determine if your current contract language creates a legal conflict. Do not wait until you are ready to launch to address ownership issues.

Simplify Contract Analysis with TermScore

Navigating the legal jargon of employment agreements is complex, but you don't have to do it alone. TermScore uses advanced AI to scan your employment contracts for aggressive IP assignment clauses, restrictive covenants, and ownership traps. By uploading your document to TermScore, you can instantly identify if your side projects are at risk and receive actionable advice on how to negotiate better terms. Protect your intellectual property today by ensuring your contract reflects your rights.

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