Free tool
Enter a US patent number to see the owner of record, every recorded assignment with its reel and frame, and anything in the chain that a buyer or lender would want explained.
Free, no sign-up. Reads the public USPTO assignment record for one US patent.
Short answer: the owner of a US patent is shown by the USPTO assignment record, not by the name printed on the patent. The name on the patent is the assignee at the time it issued. Every later sale, merger, or name change is recorded separately, so the current owner is whoever received the most recent recorded ownership transfer.
To check it yourself in the USPTO’s free Assignment Search:
For one patent this takes a few minutes. For a portfolio it takes days, which is the work the tool above and the full Patencial report automate.
Each recorded conveyance has the same few fields. These are the ones that matter for ownership:
Recording is voluntary, so the record can be incomplete in predictable ways. An inventor assignment may have been signed but never recorded, which is common after the America Invents Act let companies file as the applicant (see post-AIA chain of title gaps). A loan may have been repaid without a release being recorded, so the patent still looks pledged (see patent security interests and liens). And a company may have been acquired without the patent transfer ever being recorded.
None of these is necessarily a defect. Each is something a buyer, lender, or litigation funder will want documented before relying on the patent.
Look up the patent in the USPTO assignment records. The owner of record is the party that received the most recent recorded assignment, merger, or name change. If no assignment was ever recorded, the applicant named on the patent is usually the owner of record. The check on this page does that lookup for you.
Not always. Recording is not what makes an assignment valid; an unrecorded assignment can still transfer ownership between the parties. Under 35 U.S.C. 261, though, an unrecorded assignment can be void against a later buyer who paid for the patent without notice of it, unless it was recorded within three months or before that later purchase. That is why buyers and lenders rely on the recorded chain.
Since September 27, 2025, the USPTO Assignment Search inside Assignment Center has replaced the older Patent Assignment Search and Assignments on the Web tools. It is free and searches assignments recorded from 1980 onward by patent number, application number, reel and frame, or party name.
It is the USPTO’s locator for a recorded document: the reel is the volume and the frame is the page where the document starts. Every recorded assignment, security interest, and release has one, which makes it the standard way to cite a specific conveyance.
It runs the same checks as the full Patencial report against the recorded assignments: inventors with no recorded assignment, breaks in the chain, recordings made late, security interests with no matching release, and unusual conveyances such as court orders or partial interests. Each flag describes what in the record triggered it.
No. A flag means the public record does not show something a buyer would expect to see. Many flags have innocent explanations, such as an assignment that was signed but never recorded, or a loan that was repaid without a release being filed. Each flag is a question for counsel to resolve, not a conclusion.
Patent chain of title verification
Reconstruct ownership from the named inventors to the current assignee, with every defect cited to a USPTO record.
Read guide35 U.S.C. 261: patent assignments and recording
What Section 261 requires for a valid assignment, and why the three-month recording window decides priority.
Read guidePost-AIA chain of title gaps
How assignee filing under the America Invents Act can leave an inventor assignment unrecorded, and how to find the gap.
Read guidePatent security interests and liens
How a pledged patent shows up in the USPTO record, why an unreleased lien blocks a clean transfer, and what lenders check.
Read guideResearch: what the USPTO record shows for 500 random patents
Unreleased liens, inventors missing from the record, late recordings, and lapsed patents in a random sample of 2020 grants.
Read guideHow to buy a patent
The patent purchase process start to finish, with the due diligence checklist buyers run before closing.
Read guidePatent due diligence for M&A
What patent diligence checks before a deal closes, starting with clean ownership of every patent.
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