Invention Assignment Agreement: Who Owns What You Create
An invention assignment agreement determines who owns IP created during employment, contracting, or co-founding. Without one, disputes over ownership can destroy companies and partnerships. Here is what you need to know.
Key Takeaway
An invention assignment agreement is a legal contract that transfers ownership of inventions from the creator to another party — typically an employer or company. Without one, the default position in most jurisdictions is that the inventor owns their invention. Blockchain timestamps of your invention documentation provide court-ready evidence of when you created it — critical if ownership is ever disputed.
In This Guide
Invention assignment agreements are among the most important — and most overlooked — contracts in any technology company. They determine who owns the intellectual property that is your company’s core value. Get them wrong, and you may find that your most valuable assets belong to a former employee, a contractor, or a co-founder who has since left.
This guide explains what invention assignment agreements are, when you need them, what they should contain, and how to use blockchain timestamps to create an unambiguous record of when inventions were created — which becomes critical evidence if ownership is ever disputed.
1. What Is an Invention Assignment Agreement?
An invention assignment agreement (also called an IP assignment agreement or PIIA — Proprietary Information and Inventions Agreement) is a contract in which an inventor agrees to transfer ownership of inventions they create to another party, usually their employer.
The core mechanism: without an assignment, the default rule in most jurisdictions is that inventors own their inventions, even if they created them using company resources and during company time. An invention assignment agreement changes this — transferring ownership to the company at the moment of creation.
What Gets Assigned
The agreement typically also includes confidentiality obligations, restricting employees from disclosing proprietary information. This is why these agreements are often bundled with NDAs into a single document.
2. When Do You Need an Invention Assignment Agreement?
Any organisation that creates, develops, or relies on intellectual property should have invention assignment agreements. This includes:
Technology startups
Every employee and contractor should sign one before starting work
Co-founding teams
Co-founder IP assignments should happen at company formation, not later
R&D organisations
Research teams creating patentable inventions need clear ownership records
Software companies
Code is copyright — developers should assign rights to their employer
Universities
Often required for student and staff inventions commercialised through TTOs
Any company hiring contractors
Contractors own work product by default — assignment must be explicit
When investors ask about IP ownership
During due diligence for fundraising, investors will check that your company owns all material IP. Missing invention assignment agreements from founders or early employees are a common deal-breaker. Fix this early — it gets harder and more expensive to obtain assignments from people who have already left the company.
3. Key Clauses Every Invention Assignment Agreement Should Include
A well-drafted invention assignment agreement should cover these essential areas:
1. Assignment Clause
The core provision — the inventor assigns to the company all right, title, and interest in inventions created during the employment period. Should specify whether assignment is prospective (covers future inventions) and retrospective (covers inventions created before signing, during prior employment).
2. Scope of Inventions Covered
Define which inventions are covered. Typically: inventions related to the company’s business, created using company resources, or created during employment. Most jurisdictions limit the scope — some protect employees from assigning inventions created entirely on personal time with no connection to company business.
3. Prior Inventions Carve-Out
A list (usually as a schedule) of inventions the employee created before joining that are explicitly excluded from assignment. This protects employees’ pre-existing IP and prevents disputes later. Always insist on a prior inventions schedule at signing.
4. Disclosure Obligation
The employee must promptly disclose all inventions created during their employment, so the company can decide whether to pursue patent protection or treat them as trade secrets. Failure to disclose is often a breach of contract.
5. Assistance and Cooperation
The employee agrees to assist the company in obtaining patents or registrations, including signing documents, even after their employment ends. This is critical for patent applications that may be filed years after the invention was created.
6. Moral Rights Waiver
In the UK and EU, creators retain moral rights (the right to be identified as creator and to object to derogatory treatment) even when economic rights are assigned. A waiver of moral rights is usually included to give the company full freedom to use the work.
7. Confidentiality Obligations
The employee agrees to keep confidential all proprietary information, trade secrets, and know-how, both during and after employment. Usually combined with a non-disclosure clause that survives termination of the employment agreement.
4. Employee vs Contractor: Default IP Ownership Rules
The default IP ownership rules differ significantly between employees and independent contractors — and the rules differ by jurisdiction.
| Situation | UK Default | US Default |
|---|---|---|
| Employee — job duties include inventing | Employer owns | Employer owns (work for hire) |
| Employee — invents outside job duties | Employee owns | Employee owns (unless assigned) |
| Independent contractor | Contractor owns | Contractor owns |
| Director of a company | Fiduciary duty — usually company | Depends on agreement |
| Co-founder | Founder owns unless assigned | Founder owns unless assigned |
Critical risk: contractors
A contractor who builds your core product owns the IP unless they have signed an invention assignment (or work-made-for-hire agreement in the US). This is a very common mistake in early-stage startups that use contractors before formalising their legal structure. If you have or have had contractors, audit your agreements now.
For employees in the UK, the Patents Act 1977 provides some statutory protection — employers automatically own inventions made in the normal course of employment. However, an explicit assignment agreement removes ambiguity and is strongly recommended.
5. Co-Founder Invention Assignment
Co-founder IP assignment is one of the most critical — and most commonly deferred — tasks for early-stage companies. The problem: when co-founders split up (and many do), unassigned IP can mean a departing founder retains ownership of core technology.
What should happen at company formation
Every co-founder should assign all pre-existing relevant IP to the company and agree that all future IP created for the company will be automatically assigned. This is typically done in the founders’ agreement or as a separate IP assignment deed.
What “vesting with assignment” means
Many founders’ agreements include both IP assignment and share vesting — shares vest over time to ensure each co-founder has an incentive to stay. IP assignment should be immediate and complete; it should not be tied to vesting schedules.
What happens when a co-founder leaves
If a proper assignment was in place from the start, the company owns all IP regardless of the co-founder’s departure. The departing founder may retain unvested shares, but the IP stays with the company. Without assignment, departing founders can hold the company’s core technology hostage.
See also: IP protection before patent — how to secure invention rights during the early stages before formal filing.
6. How Blockchain Timestamps Strengthen Invention Assignment Agreements
An invention assignment agreement says who owns an invention. A blockchain timestamp provides court-ready evidence of when the invention existed and what it consisted of at that moment. Together, they create a strong ownership record.
Establishing the invention date
When an employee creates an invention, a blockchain timestamp of the invention disclosure documents proves the exact date of creation. This matters in disputes about whether an invention was created before or after an assignment agreement was signed — or before or after an employee joined or left.
Proving what was disclosed
In ownership disputes, one party often claims they disclosed more (or less) than they actually did. A blockchain-timestamped invention disclosure is immutable — its contents cannot be changed or disputed. The document hash proves the exact content as of the timestamp.
Prior inventions carve-out evidence
If an employee claims certain IP pre-dates their employment and should be excluded from assignment, a blockchain timestamp of early design documents, code commits, or prototypes provides verifiable proof of when those ideas existed — strengthening or refuting the carve-out claim.
Investor due diligence
When investors conduct IP due diligence, being able to show blockchain-timestamped records of invention disclosures alongside signed assignment agreements demonstrates a serious, documented approach to IP ownership — which is exactly what investors want to see.
Learn more about building a complete IP protection strategy: how to protect intellectual property.
Create a Blockchain-Verified Invention Record Today
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Frequently Asked Questions
What is an invention assignment agreement?
An invention assignment agreement is a contract in which an inventor (typically an employee or contractor) transfers ownership of inventions they create to another party (typically their employer or a company). It ensures the company owns IP created on company time or using company resources, rather than the individual inventor.
Does an employer automatically own inventions made by employees?
In the UK, employers automatically own inventions made by employees in the normal course of their duties (Patents Act 1977). However, this does not cover inventions created outside job duties, and does not cover copyright works or contractor work. An explicit invention assignment agreement removes all ambiguity and is strongly recommended regardless of statutory protections.
What happens if a contractor creates IP without an assignment agreement?
The contractor owns the IP by default — even if you paid for the work. This is one of the most common and costly IP mistakes made by startups. To fix it, you need the contractor to sign an assignment agreement after the fact, which they may not agree to (or may charge for). Always get assignment agreements signed before work begins.
Can an invention assignment agreement be challenged?
Yes, if it is too broad. Many jurisdictions limit the scope of what can be assigned — for example, California law prohibits employers from requiring assignment of inventions created entirely on personal time with no connection to company business. A well-drafted agreement should respect these limits. An overly broad agreement may be unenforceable in its entirety.
Why do investors care about invention assignment agreements?
Investors conduct IP due diligence before investing. They want to confirm the company actually owns all material IP, especially from founders and early employees. Missing assignments are a common deal-blocker. VCs typically require all employees and contractors to have signed PIIAs (Proprietary Information and Inventions Agreements) as a condition of investment.