Search recorded USPTO patent assignment records by application number, patent number, or publication number
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Search by: Application 14/263,610 · Patent 11,646,472 · Publication US20250087686A1
Find recorded ownership transfers, security interests, releases, corrective assignments, and chain-of-title events for US patents and patent applications.
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Search by US patent application number, patent number, or publication number.
Ownership transfers, security interests, releases, and name changes are categorized and ordered chronologically.
See the full assignment timeline, encumbrances, party directory, and apparent current owner.
Use this patent assignment search tool to review the recorded assignment history for a US patent or patent application. This tool helps you quickly see whether rights were transferred from inventors to a company, whether a lender recorded a security interest, whether that interest was later released, and whether name changes, mergers, or corrective filings appear in the public assignment record.
With this tool, you can:
A patent assignment is a transfer of ownership rights in a patent or patent application. In many cases, inventors assign their rights to their employer or to a startup they formed. Patent rights can also later be transferred through an asset sale, corporate acquisition, merger, internal reorganization, or other business transaction.
Many of these transfers are recorded with the USPTO Assignment Recordation Branch. Those records can help users understand the public chain of title associated with a patent asset.
A recorded assignment may involve:
If you want to know who appears to own a patent, start by searching the patent assignment history using one of the following identifiers:
This tool then retrieves the recorded assignment events associated with that asset and organizes them into a simpler ownership view.
In many cases, the current owner can be inferred from the most recent ownership-type records. However, users should be careful: the USPTO assignment database is extremely useful, but it does not always provide a complete legal determination of current ownership.
This tool is designed to help users understand the main categories of recorded patent assignment activity. Depending on the record, results may include:
Assignments from inventors to companies, from one company to another, or as part of broader business transactions.
Financing records where patent rights are pledged as collateral or otherwise encumbered.
Recorded documents showing that a previously recorded security interest or similar encumbrance has been released.
Records that reflect a company name change, merger, reorganization, or similar corporate event that affects how ownership appears in the public record.
Documents filed to correct errors in earlier assignment records, such as party names, property descriptions, or execution details.
A chronological view of recorded transactions affecting apparent ownership history.
USPTO assignment records typically include a short conveyance text describing the nature of the filing. This tool normalizes those recorded descriptions into more understandable categories so users can more quickly interpret what happened.
For example, a record may be categorized as:
This makes it easier to review assignment history without needing to interpret raw record text line by line.
When reviewing a patent's assignment history, it helps to look at the records as a sequence rather than as isolated entries.
A common pattern might look like this:
Inventors assign the application to a startup or employer
This is often the earliest ownership transfer.
The company grants a security interest to a lender
This does not necessarily mean the lender became the operating owner. It often means the patent was used as collateral.
The company changes its name or merges into another entity
Later records may reflect that the patent rights now sit under a different legal name.
The lender files a release
This indicates that a previously recorded security interest was later released.
A corrective assignment is filed
This may fix an earlier record that contained an error.
The most useful question is usually not just “what is the latest filing,” but rather “what sequence of recorded ownership-related events appears in the record?”
Chain of title refers to the sequence of recorded transfers and related events affecting ownership rights in a patent or patent application.
For patents, chain of title can matter in:
A clean and understandable chain of title helps users assess whether ownership appears consistent across time. If the chain is incomplete, inconsistent, or contains unusual financing records, that may merit closer review.
A security interest usually means the patent rights were pledged as collateral in a financing arrangement. It does not necessarily mean that the lender became the patent owner in the ordinary business sense.
That distinction matters. A patent assignment database may show a lender-related record, but users often care more about which company appears to be the operating owner of the patent portfolio.
That is why security-interest-type records should usually be read differently from ordinary ownership-transfer records.
This tool uses the phrase apparent operating assignee to describe the entity that appears to hold operating ownership based primarily on recorded ownership-type events, while de-emphasizing records that appear to reflect only collateral or financing arrangements.
This is meant to be a practical interpretation aid, not a definitive legal conclusion.
For example:
This concept is useful when the raw assignment record includes a mixture of ownership transfers and financing-related filings.
Here is a simplified example of how patent assignment history may look:
Step 1
Inventors assign rights to Example Biotech, Inc.
This is the original transfer from the inventors to the company.
Step 2
Example Biotech grants a security interest to First Bank
This suggests the patent may have been used as collateral in a financing arrangement.
Step 3
Example Biotech, Inc. changes name to Example Therapeutics, Inc.
The operating owner may be the same business under a new legal name.
Step 4
First Bank records a release
The prior security interest was released.
Step 5
A corrective assignment is later recorded
The corrective record fixes an error in one of the earlier filings.
In a case like this, the apparent operating assignee may still be the company, not the lender, even though the lender appears in the assignment history.
A patent assignment is generally a transfer of ownership. A patent license, by contrast, is permission to use patented technology under agreed terms.
This matters because the USPTO assignment database is primarily about recorded ownership-related transactions, not every commercial arrangement involving patent rights. A company may license patent rights without that license appearing in the same way as a recorded assignment.
So if you are trying to understand complete commercial rights, the public assignment record may be helpful but incomplete.
USPTO assignment records are extremely useful, but users should understand their limits.
Not every relevant ownership or commercial arrangement is necessarily reflected in the public assignment record.
A recorded assignment helps show what was filed, but it is not a substitute for legal due diligence or a formal ownership opinion.
There may be delays between execution, recordation, and later corrective filings.
Mergers, reorganizations, and internal transfers may not always be obvious from a quick glance at one record.
A security interest may appear in the data even though operating ownership did not change.
Because of that, this tool should be treated as a strong starting point for patent ownership review, not the last word in every case.
Different users have different identifiers available.
Useful when reviewing a pending application or prosecution file.
Useful when checking the ownership history of an issued patent.
Useful when the application is known by publication rather than by issued patent number.
Allowing all three makes the tool more flexible for patent attorneys, diligence teams, investors, founders, and researchers.
This patent assignment lookup tool is useful for:
Anyone trying to answer “who owns this patent?” or “what happened in the recorded assignment history?” can use the tool as a first-pass public-record review.
In-depth guides on patent ownership, assignment records, and related topics.
A guide to using USPTO assignment records to identify who appears to own a patent.
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How security interests work in patent records and why they differ from ownership transfers.
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Step-by-step guidance on interpreting the sequence of recorded assignment events.
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The key differences between transferring patent ownership and licensing patent rights.
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What chain of title means for patents and why it matters in diligence and transactions.
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How the USPTO organizes recorded assignment documents using reel and frame numbers.
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Key steps for reviewing patent ownership as part of an acquisition or investment.
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How to look up assignment records using an application number instead of a patent number.
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Data sourced from public USPTO assignment records. This tool provides informational summaries and should not be relied upon as legal advice or a definitive title opinion. Always verify patent ownership independently, especially where unrecorded transfers, court orders, or other off-record events may apply.