Find the prior art a patent cites and how the patent talks about it
A patent lists earlier documents in two places: the references cited on its front page, which can come from the applicant or the examiner, and the background section, where the applicant describes earlier approaches and their shortcomings. Ask Search+ "Which earlier patents does this patent cite, and how does the background describe them?" and open the citations to read both.
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Last updated October 2026
How to find prior art citations with Search+
- Upload the patent and the cited documents you have
Add the patent. If you have copies of key cited references, add them too, including scanned ones, so you can ask what they actually disclose.
- Ask about the reference list and the background separately
First ask which references are listed on the patent. Then ask how the background section characterizes earlier work. They answer different questions.
- Check a reference against the claims
Ask what a cited reference describes about a feature, then ask how the patent's claims differ on that feature. Read both citations before drawing conclusions.
Questions to ask about prior art citations
Which patent documents and non-patent publications are listed as references cited?
Which earlier approaches does the background section describe, and what problems does it say they have?
Does this patent mention the earlier patent by the same inventor, and where?
Which journal articles or standards does the patent cite?
Which references are cited by most of the patents in this workspace?
What to look for in prior art citations
The reference list records documents considered during examination; the background section is the applicant's own description of earlier work. They overlap but are not the same.
Some patent offices mark which references were cited by the examiner and which by the applicant. If the patent shows this, it tells you which documents the examiner found relevant.
Some offices publish search reports that label each reference by how relevant it is to the claims. If you have the search report, add it to the workspace.
Applicants sometimes cite many documents. Ask what a reference actually discloses before treating it as close to the invention.
Each answer cites the excerpt it relied on, with a page or section reference when the document gives one.
With the patent and its references in one workspace, ask across all of them or narrow to one.
Citation wording and what to ask next
The labels below are as printed on US patents. Other offices, such as the EPO, use different headings and publish separate search reports.
| Wording you may see | What it usually signals | A follow-up question |
|---|---|---|
| "References Cited" | The front-page list of documents | Which of these are patents and which are publications? |
| "Other Publications" | Non-patent literature such as articles | Which articles are cited, and from what years? |
| "cited by examiner" | A reference the examiner relied on | Which references did the examiner cite? |
| "Description of the Related Art" | The applicant's view of earlier work | What shortcomings does the patent attribute to earlier approaches? |
| "incorporated by reference" | Another document's content treated as part of this one, a practice mainly found in US patents | Which documents are incorporated by reference? |
What are prior art citations in a patent?
Prior art citations are the earlier patents, applications and publications a patent refers to, both in its list of references cited during examination and in the background where the applicant describes existing technology.
Prior art citation questions
Can Search+ list the references a patent cites?
Can it find prior art that the patent does not cite?
Can it tell me what a cited reference discloses?
Is this a patentability or validity opinion?
What if a cited reference is a scan?
Can an answer miss a reference?
Know what the patent was measured against
Start a workspace, upload the patent and its key references, and ask what each one cites and discloses.
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