# Can My Employer Claim My Side Project? > Can my employer own my side project? The three-question test, why ‘my own laptop at home’ isn't enough, state-law protections, and a hygiene checklist. Guide | Author: Lidiia Levitska | Source: Intellectual Property Law (outsideipcounsel.com) Canonical: https://outsideipcounsel.com/guides/can-my-employer-own-my-side-project/
Quick answer: Your employer can claim your side project if your invention-assignment agreement reaches it — and most reach anything made during employment, on or off the clock. The analysis comes down to three questions: what did you sign, did you use any employer time, equipment, facilities, or trade secrets, and does the project relate to the employer's business or your work for it. About ten states ([California Labor Code § 2870](https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=LAB§ionNum=2870), plus Washington, Illinois, Minnesota, and others) protect projects that are clean on all three — but "built at home on my own laptop" is not enough by itself if the project relates to what your employer does. Clean hardware, clean hours, documented timelines, and a disclose-and-carve-out strategy are what actually keep a side project yours. This is general education, not legal advice — have an attorney licensed in your jurisdiction review your specific situation.
It's the modern builder's nightmare: you spend two years of nights and weekends on an app, it finally gets traction — and your employer's counsel sends a letter claiming the company owns it. Whether they're right is rarely decided by fairness or by who typed the code. **Can my employer own my side project?** The honest answer is "it depends on three questions," and this guide walks through them, the state statutes that protect some projects, the traps that catch developers specifically, and the hygiene checklist that keeps ownership clean. ## The three-question analysis Every side-project ownership dispute reduces to some version of these three questions. You need good answers to **all three**, not just one. ### 1. What does your agreement actually say? Start with the invention-assignment agreement (PIIA) you signed at hiring — dig out the actual document, because memory is not a defense. The key variables: - **Temporal scope.** Most assignments cover inventions conceived or reduced to practice "during the period of employment" — which includes 11 p.m. on a Saturday. A few are narrower ("in the course of employment"); read yours. - **Subject-matter scope.** Some assign everything; better ones track the statutory carve-outs. - **Disclosure duties.** Many require you to disclose *all* inventions, even ones you claim are excluded. - **Prior-inventions schedule.** Anything you listed there before starting is presumptively yours. The clause-by-clause anatomy is in [invention assignment agreements: what you're actually signing away](/guides/invention-assignment-agreements/). If you never signed anything, the defaults are far friendlier to you — inventions belong to the inventor, per the [employee IP pillar](/guides/who-owns-what-you-create-at-work/) — but confirm there's truly nothing in your offer letter, handbook acknowledgment, or onboarding click-throughs. ### 2. Did you use employer time, equipment, facilities, or trade secrets? This is the resource question, and it's binary in effect: **any** meaningful use of company resources contaminates the project. That includes the obvious (coding at your desk during work hours, using your work MacBook) and the less obvious (the company's cloud credits, an internal library, a dataset you exported, architectural ideas that are themselves confidential, even lengthy brainstorming in the office). Use of resources can hand the employer ownership under the agreement — or, at minimum, a **shop right**: a royalty-free, nonexclusive license to use your invention even if you keep title. ### 3. Does it relate to the employer's business or to your work? The question everyone underestimates. Even in the most protective states, the employer can claim inventions that **relate to the employer's business or actual or demonstrably anticipated R&D**, or that **result from work you performed** for the employer. "Relatedness" is judged from the employer's side of the table, and modern tech employers describe their business broadly. A backend engineer at a fintech building a budgeting app is *related*. An ML researcher building any ML tool is probably *related*. The same engineer building a surf-forecasting app is likely safe. If your side project is in your professional field — which, for most people, is exactly the project they're able to build — assume relatedness is contested. ## Why "on my own laptop at home" isn't a safe harbor The most common misconception deserves its own section: hardware and hours answer **question two only**. You can be flawless on resources — personal laptop, personal accounts, midnight commits — and still lose on **question one** (a broad clause in a state without carve-out statutes) or **question three** (relatedness). The statutes below were written precisely this way: own-time-own-equipment is the *entry condition* for protection, and relatedness is the *exception that survives it*. So treat clean hardware as necessary hygiene, never as the whole defense. ## The state statutes that protect unrelated projects Roughly ten states void contract clauses that overreach into genuinely personal inventions. **California Labor Code § 2870** is the template: an assignment provision doesn't apply to an invention developed **entirely on your own time without employer equipment, supplies, facilities, or trade-secret information** — unless it relates to the employer's business or demonstrably anticipated R&D, or results from your work for the employer. Washington (RCW 49.44.140), Illinois, Minnesota, North Carolina, New Jersey, Delaware, and Kansas follow the same pattern, New York adopted its version in 2023, and Utah has a differently structured statute of its own. Three practical notes: 1. **The protection is self-executing** — a clause claiming protected inventions is void as to them, and in carve-out states the agreement must generally notify you of the exception. 2. **The exceptions do the real work.** Most litigated cases turn on relatedness, not on whose laptop it was. 3. **No statute? Contract controls.** In the majority of states with no such law, a broad "everything during employment" clause can be enforceable even against a truly unrelated weekend project. The full statutory mechanics, with worked California examples, are in [California Labor Code § 2870, explained](/guides/california-labor-code-2870/). ## Developer-specific traps Software builders hit hazards that other inventors don't: - **Company GitHub and CI.** Pushing side-project code to an org account, running it through employer CI, or reusing an employer-paid IDE license or cloud subscription is "employer equipment/facilities" use. Personal repo, personal account, personal billing — always. - **Cross-pollinated code.** Copying even utility snippets from work code into your project (or vice versa — pasting your side project into work code can trigger the assignment or muddy the timeline) contaminates both directions. Keep the codebases hermetically separate; see [how to protect source code](/guides/how-to-protect-source-code/) for why employers audit exactly this. - **Open-source policies.** Many employers require approval for OSS contributions and route them through a company CLA. Your weekend contributions to public projects may technically fall inside your assignment clause unless the policy or a carve-out says otherwise — ask, and get the answer in writing. - **AI-assisted work.** If you use your employer's AI coding tools or accounts, the prompts and outputs may run through employer systems and licenses, layering the resource question with fresh authorship questions — see [who owns AI-generated code](/guides/who-owns-ai-generated-code/). ## The hygiene checklist If you want the project to be defensibly yours, run it like the dispute already happened: 1. **Read your agreement first** — before line one of code, not after launch. 2. **Separate everything**: personal hardware, personal email/GitHub/cloud accounts, personal payment methods. No exceptions "just this once." 3. **Never touch work hours or work systems.** Not the office Wi-Fi for a deploy, not the standup lull for a bugfix. 4. **Use zero employer confidential information** — code, data, roadmaps, customer knowledge, internal architecture patterns. 5. **Document the timeline.** Commit history, dated design notes, domain registrations. In a dispute, contemporaneous records beat testimony every time. 6. **Disclose and carve out.** If your agreement requires disclosure, comply — and turn it to your advantage by requesting a **written acknowledgment** that the named project is excluded. If you're job-hunting, list the project on the **prior-inventions schedule** of the next PIIA. 7. **Get waivers in writing.** A manager's verbal "sure, that's fine" is worth what it's written on. An email from someone with authority — or better, a signed carve-out — is real protection. ## Moonlighting policy vs. IP ownership: two different issues Don't conflate two separate questions. A **moonlighting or outside-activities policy** governs whether you're *allowed* to do outside work (conflicts of interest, approvals, time commitments); violating it risks your job. **IP ownership** governs who owns what you built; violating those rules risks the project. You can be fired for undisclosed moonlighting even when the project is legally yours — and you can keep your job while the company owns the project. Check both the PIIA *and* the handbook. ## If a dispute happens anyway When employers claim side projects, the litigation toolkit looks like this: breach of the assignment agreement, misappropriation of trade secrets if any confidential information leaked in, and a request for a **constructive trust** — an equitable remedy in which the court declares you held the project (and its revenue, and possibly the company you formed around it) for your employer all along. Where the invention is yours but you used company resources, courts may award the employer a **shop right** rather than ownership. Your best evidence is everything from the hygiene checklist; your worst evidence is a blank prior-inventions schedule, work-hours commits, and a repo on the company org. For how courts have resolved invention-ownership fights like these, browse the [patent case-law archive](/topics/patents/). And the highest-stakes version of the scenario — you quit to pursue the side project full-time, possibly in your employer's market — adds resignation timing, holdover clauses, and trade-secret exposure to the mix. Before you give notice, read [quitting to start a competitor](/guides/quitting-to-start-a-competitor/). ## The bottom line Your employer can claim your side project when the agreement reaches it, when company resources touched it, or when it relates to the company's business — and the last of these is the trap, because "own laptop at home" answers only the middle question. Statutes like California's § 2870 protect genuinely unrelated own-time projects, but a project in your own professional field usually has to survive a relatedness fight. Build like the dispute is coming: clean hardware, clean hours, zero confidential information, a documented timeline, and a disclosed, written carve-out. For the broader map of who owns what across your working life, start with the [employee IP pillar](/guides/who-owns-what-you-create-at-work/). --- *This article is general legal information for educational purposes only. It is not legal advice, does not create an attorney-client relationship, and may not reflect the most current law in your area. Side-project ownership disputes turn on specific facts and exact contract language. For advice about your situation, consult an attorney licensed in your jurisdiction.* ## Frequently asked questions ### Can my employer own something I built on my own time? Yes, in many situations. Most invention-assignment agreements reach inventions made during your employment period, not just during work hours. Whether the claim sticks depends on three things: what your agreement says, whether you used any employer time, equipment, facilities, or confidential information, and whether the project relates to your employer's business or the work you do for it. In roughly ten states, statutes like California Labor Code § 2870 void assignment of projects that are clean on all three counts — but a project in your employer's field usually fails the relatedness test even there. ### Is my side project safe if I only use my personal laptop at home? Not automatically. Separate hardware and off-hours work satisfy only part of the analysis. The statutory carve-outs and most agreements still let the employer claim inventions that relate to its business or actual or demonstrably anticipated research and development, or that result from your work for it — regardless of whose laptop you used. A payments engineer building a payments tool at home on personal equipment is still building something related to the employer's business. Own hardware and own time are necessary hygiene, not a complete defense. ### Do I have to tell my employer about my side project? Check your agreement — many PIIAs impose a duty to disclose all inventions made during employment, even ones you believe are excluded, so the company can evaluate the claim. Separately, many employers have moonlighting or outside-activity policies requiring approval for outside work regardless of who owns it. Disclosure feels risky, but a documented disclosure with a written acknowledgment that the project is excluded is far stronger protection than secrecy, which can support bad-faith arguments and even a constructive trust if a dispute erupts later. ### What happens if my employer claims my side project after it takes off? The dispute typically plays out as a contract and trade-secret fight. The employer will point to the assignment clause, any use of company resources or confidential information, and relatedness to its business; remedies can include a constructive trust over the project and its proceeds, meaning a court treats you as having held it for the employer all along. If you used company time or equipment but the invention is otherwise yours, the employer may get a shop right — a royalty-free license — instead of ownership. Contemporaneous records of when and how you built it are usually the deciding evidence.