USPTO patent search: US patents and applications
Search runs at search.patentassist.ai: AI agentic search, classic field search and full text across the USPTO, EPO and IP India. Free to start, no signup needed.
USPTO patent search with an AI agent
Search granted US patents and published applications without learning a query syntax. Describe the invention in plain English and the AI agent writes the queries, follows the strongest leads and returns a ranked shortlist of prior art with the reason each one matched. The data comes from the USPTO's own Open Data Portal.
What you can search
- Plain-language description of the invention (AI agent)
- Title, applicant and inventor
- Examiner, useful for narrowing to an art unit
- CPC classification
- Application number and patent number
- Filing date range
- AND, OR and NOT between fields
What each record shows
- Abstract, claims and full description
- CPC classes, examiner and group art unit
- Continuity data and foreign priority claims
- Assignment history and transaction history
- Patent term adjustment
- File wrapper documents you can download
Compared with Patent Public Search and Google Patents
The USPTO's Patent Public Search expects you to write the Boolean query yourself, and from November 7, 2026 it needs a USPTO account. Google Patents is a general keyword search. PatentAssist search starts from a plain-language description, lets an AI agent write and refine the queries, and returns ranked US, European and Indian prior art with the reason each document matched, plus the prosecution data on each US record: continuity, assignments, transaction history and file wrapper documents.
| Feature | PatentAssist search | USPTO Patent Public Search | Google Patents |
|---|---|---|---|
| Run by | PatentAssist, using USPTO Open Data Portal data | The USPTO | |
| US documents | Granted patents and pre-grant publications | All US patents and published applications | US patents and publications, with full text |
| Other offices | EPO and IP India in the same search | US only | 100+ offices; full text from 22 |
| How you search | Describe the invention and an AI agent plans the queries and ranks the results with reasons; or use classic field search | Full-text search with operators, plus basic and advanced forms | Keyword search with machine translation of non-English documents |
| Account | None needed to start; free with a weekly search allowance | USPTO account sign-in required from November 7, 2026 | None |
Reading a US patent number
You can paste any of these into the search box. The kind code at the end tells you what the document is (MPEP 901.04(a)).
- Granted utility patent
- US 11,234,567 B2
- B1: no earlier publication. B2: published as an application first.
- Pre-grant publication
- US 2023/0123456 A1
- Publication year, then a serial number.
- Design and plant patents
- US D123,456 S · US PP12,345 P3
- D prefix for designs, PP for plants.
Found the closest prior art? PatentAssist can draft the US application around it, with claims, description and patent drawings. For a structured report, see prior art search. Guides: how to file a US provisional application, USPTO patent fees, USPTO maintenance fees, how to respond to a USPTO office action and how to read a PCT search report and written opinion.
USPTO patent search: questions
Is this a free alternative to USPTO Patent Public Search?
Yes. PatentAssist search is free, needs no account to start, and adds what Patent Public Search doesn't have: an AI agent that turns a plain-language description of the invention into queries, reads the closest documents and ranks them with the reason each matched. It also searches EPO and IP India records from the same box. From November 7, 2026, Patent Public Search requires a USPTO account sign-in.
Which US documents can I search?
Granted US patents and pre-grant publications, using data from the USPTO Open Data Portal. Provisional applications are never published (35 U.S.C. 122(b)(2)(A)(iii)), so no public database can show them. Applications that are still unpublished are not searchable either.
Can I search the full text of the claims?
Classic search covers title, applicant, inventor, examiner, CPC class and application and patent numbers, with a filing date range. It is not a Boolean search of claim text. You can read the full claims and description on every record, and the AI agent reads abstracts when it ranks results.
What do the letters after a US patent number mean?
They are kind codes (MPEP 901.04(a)). A1 is a pre-grant publication. B1 is a patent with no earlier pre-grant publication, and B2 is a patent that was published as an application first. S is a design patent, P2 and P3 are plant patents, and E is a reissue.
How long does a US patent last?
A utility patent ends 20 years from its filing date, or from the earliest non-provisional application it claims the benefit of (35 U.S.C. 154(a)(2)), as long as maintenance fees are paid 3.5, 7.5 and 11.5 years after grant (35 U.S.C. 41(b)). A design patent lasts 15 years from grant (35 U.S.C. 173) and has no maintenance fees.
Does a search here count as a patentability or FTO opinion?
No. It finds and ranks documents. Judging novelty, obviousness or infringement against what you find is work for a registered patent attorney or agent.
Search other offices:
Sources, checked October 25, 2026: USPTO Patent Public Search, USPTO launch release (2022), Google Patents coverage, MPEP 901.04(a), 35 U.S.C. 41, 122, 154 and 173 (MPEP Appendix L). General information, not legal advice.