Can an employer enforce an NDA to claim ownership of side projects built on personal time?

Can employers claim your side projects? Learn the legal limits of IP assignment clauses and how to protect your work. Analyze your contract with TermScore.

October 27, 2026TermScore Legal Intelligence GroupStatutory & Corpus Verified655 words

Can an employer enforce an NDA to claim ownership of side projects?

An employer cannot automatically claim ownership of side projects developed entirely on your own time, using your own equipment, and unrelated to the company’s business. While many employment contracts contain broad Intellectual Property (IP) assignment clauses, these are frequently limited by state law and common law principles that protect an employee's right to innovate outside of their professional duties.

The Legal Framework of IP Assignment

Most employment agreements include an "Inventions Assignment" clause. This is distinct from an NDA, which protects trade secrets. An IP assignment clause dictates who owns the "fruits of your labor." If a contract is drafted too broadly, it may attempt to claim everything you create during the term of your employment, regardless of when or how it was built.

The "Nexus" Requirement

For an employer to claim ownership, there must be a direct nexus between the project and the employer. Courts typically evaluate three factors:

  • Scope of Employment: Did the project result from tasks you were hired to perform?
  • Company Resources: Did you use company laptops, servers, proprietary software, or paid time to build the project?
  • Business Relevance: Does the project compete with or directly relate to the employer's current or anticipated business activities?

Key takeaway: If your side project is a mobile game and you are a backend engineer for a fintech company, the "business relevance" factor is likely in your favor. If you are building a fintech tool, your employer has a much stronger claim.

State-Specific Protections

Jurisdiction is the most critical factor in determining the enforceability of these clauses. Several states have enacted "Employee Invention Statutes" that explicitly limit an employer's reach.

StateKey Protection
CaliforniaLabor Code 2870 prohibits employers from claiming inventions developed on personal time without company resources.
WashingtonRCW 49.44.140 protects inventions developed entirely on personal time that do not relate to the employer's business.
IllinoisEmployee Patent Act prevents employers from requiring assignment of inventions developed on personal time.

Action Item: Check your employment contract for a "Notice" provision. In states like California, employers are legally required to provide a written notice of these protections when you sign your employment agreement.

Red Flags in Your Employment Contract

When reviewing your contract, look for language that signals an overreach. If you see the following, your side projects may be at risk:

  • "All-Encompassing" Language: Phrases like "any and all inventions conceived during the term of employment" without qualifying language regarding company time or resources.
  • Broad Definitions of "Business": Definitions that include "any business the Company may enter into in the future," which effectively gives the employer a claim to almost anything.
  • Lack of Exclusions: The absence of a schedule or appendix where you can list "Prior Inventions" or "Excluded Projects."

Action Item: If you have an existing side project, ensure it is listed in an "Excluded Inventions" exhibit attached to your contract. If it isn't, consult with legal counsel about adding an addendum.

Best Practices to Protect Your Work

To ensure your side projects remain yours, you must maintain a "clean room" environment. Follow these steps to mitigate risk:

  1. Use Personal Hardware: Never use a company-issued laptop, tablet, or phone for side project development.
  2. Separate Networks: Do not use company VPNs or cloud storage accounts (like company-managed AWS or GitHub Enterprise) for personal code.
  3. Document Everything: Keep a log of hours worked on your project. If challenged, you need to prove the work occurred outside of your 9-to-5.
  4. Avoid Company IP: Do not use proprietary libraries, internal documentation, or trade secrets belonging to your employer.

Key takeaway: The burden of proof often shifts to the employee to demonstrate that a project was created independently. Documentation is your primary defense in litigation.

How TermScore Can Help

Navigating the nuances of IP assignment clauses is complex, and standard legal advice can be prohibitively expensive. TermScore uses advanced AI to instantly analyze your employment contract, identifying overly broad IP assignment clauses and highlighting potential risks to your personal projects. By flagging restrictive language before you sign, TermScore empowers you to negotiate better terms and protect your intellectual property with confidence.

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Researched and cross-referenced against statutory codes, judicial rulings, and TermScore's proprietary Corpus of 100,000+ analyzed contracts. Our intelligence unit continuously audits contract enforceability and predatory clause variance across all 50 US jurisdictions.

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