With the passing of the America Invents Act, the US patent office now accepts prior art submissions from anyone. This guide will help you get through the procedure to submit prior art effectively and contribute to getting patent applications rejected.

The USPTO procedure to submit prior art before the issuance of a patent

There are several ways in which prior art can be used to invalidate a patent or a patent application. Since 2012, anyone[^1] can submit prior art before a patent gets granted, during the application phase.

The prior art references must be submitted to the US patent office in a procedure called third-party preissuance submissions (“code name:” 3PPI). This procedure is subject to §122 (e) of title 35 of the US Code.

When to submit prior art to the US patent office?

The submission has to be sent in time during the application phase:

  • no more than 6 months after the patent application was published,


  • as long as no part of the application has been rejected by the patent examiner (section 132 notice)

    whichever comes last.


  • 2013: Inventor X files for a patent
  • May 2014: the US patent office publishes the patent application (under section 122 (b))

We have three possible scenarios:

  1. The patent examiner issues a §151 notice of allowance before November 2014

    Then, it is too late to submit prior art after that notice. Prior art submissions under the third-party preissuance procedure must be made on patent applications, not granted patents.

  2. The patent examiner issues a §132 notice of rejection before November 2014

    You can still submit prior art references until November 2014, which is during a 6-month timeframe starting from the publication of the patent application (in our example, May 2014 → November 2014).

  3. The patent examiner issues a §132 notice of rejection after November 2014

    You can still submit prior art references after November 2014, until the patent examiner issues such a §132 notice.

For more information, you can refer to the USPTO’s answers on Timing of a Preissuance Submission.

Which prior art references can you submit?

Two conditions are absolutely necessary for a document to constitute prior art:

  • the document must have been made available to the public

  • the publication date is paramount in order for prior art to be relevant for challenging patent validity, so any document where the publication date is uncertain is going to have less value.[^2]

In order to constitute prior art and establish that the patent application claims something that is not new, the publication date must precede the patent application filing date and its priority date.

HOWTO submit your selected prior art references

Find relevant patent applications in the USPTO database

The US patent office classifies patent and applications in classes and subclasses. Linux Defenders maintain a list of classes relevant to software taken from the USPTO classification.

To search through the database of patent applications and monitor classes of interest, you need to learn their query format.

For instance, to search all applications related to Artificial Intelligence (class 706), query CCL/706/$.

You can also limit the query to certain timeframes. For instance, to search from January 2014 to September 2014, add to your query AND PD/1/$/2014->9/$/2014 (The $ works as a catch-all).

Submit prior art

The procedure of third party preissuance submissions is identified as “37 CFR 1.290” within the USPTO. You can submit up to three prior art references without paying fees and statement “37 CFR 1.290(g)” is selected in the submission interface. You can submit without registration. Registered filers can save a submission draft for 7 days (the application requires Java).

When you select that you submit prior art for an existing application and that the procedure is “37 CFR 1.290” you need to identify the patent application with the application number. You will also need a confirmation number, which can be found on the USPTO PAIR system. You will need this number when making your prior art submission and to track your submission.

You have to select what kind of prior art reference you submit:

  • a US patent
  • a US patent application
  • a foreign patent or patent application
  • non-patent documents

However, it should be noted that almost all examiners rely on patent and patent applications references when they reject claims so patent references should be preferred over others.


  • For all of these documents, several details will be needed, like the name of the inventor for a patent, the date of publication, the title, etc.

  • For documents other than US patents, you will need to provide a copy.

  • For documents not in English, you will need to attach a translation.

  • For each prior art reference, you need to provide the information to identify portions of the document and to expose how they are relevant to the patent.

    However, stick to the facts and the content of the prior art documents itself and don’t propose legal arguments related to the patent’s validity, it is the exclusive competence of the examiner.

    The USPTO suggests to format this information as a “claimchart” emphasising elements of the claims on the left and a concise description or quotation of relevance of the publication on the right:

    Claim 1 Publication X

    Element A

    As discussed on page 1, publication X discloses a machine that performs the same function as the machine recited in claim 1. The machine set forth in publication X includes many of the same parts discussed in the specification of this application. For example, in the first embodiment depicted in Figure 2 and discussed on page 5, the machine of publication X expressly includes element A of claim

    1. See lines 7-14 on page 5 of publication X.

    Element B

    The first embodiment also includes element B of claim 1. See lines 1-3 on page 6 of publication X.

[^1]: From the USPTO: A third-party can submit prior art, but not an individual who has a duty to disclose information with respect to the application (i.e., each individual associated with the filing and prosecution of the patent application) under 37 CFR 1.56. The party making the submission must also state that the submission complies with the requirements of 35 U.S.C. 122(e) and 37 CFR 1.290.

[^2]: Where the actual publication date of a document is not known, you will have to provide evidence to establish when the document was publicly available.