September 7, 2022

WIPO ST.26 Overview

For the first article in our Big Bang Blog Series, we thought it apt to introduce you to the new WIPO Standard ST.26 with an overview in the form of a Q&A that targets some of the most often asked questions regarding the update.


1. What is WIPO Standard ST.26? 

WIPO has implemented a new standard for nucleotide and amino acid sequence submission requirements. Compared to the former WIPO Standard ST.25, the new ST.26 includes additional sequence types and is more compatible with major sequence databases. The most recently adopted standard is available here: WIPO Standard ST.26.

2. What is the “Big-bang” date and what patent applications does it apply to?

The so-called “Big-bang” date was July 1, 2022. ST.25 remains effective for applications with a filing date prior to July 1, 2022, while new applications filed on or after July 1, 2022 must comply with ST.26, even if the priority application contains an ST.25 sequence listing.  Important note for patent applications with filing dates that “bridge” over July 1, 2022:

  • U.S. national phase applications with an international filing date before July 1, 2022 must file sequence listings in ST.25 format.
  • New U.S. continuations and divisionals filed on or after July 1, 2022 (even if they have a benefit date prior to July 1, 2022) need an ST.26-compliant sequence listing.

3. How does an applicant file a PCT application containing an ST.26 sequence listing?

ePCT has been updated to allow ST.26 compliant (XML) sequence listings to be uploaded. As of July 1, 2022, the file format options for the sequence listing part of the description will no longer include PDF and TXT, except for post-filing submission of sequence listings in relation to international applications filed prior to that date.

4. How does an applicant file an ST.26-compliant sequence listing with the USPTO?

The USPTO’s rules for submitting biological sequence data have been amended to incorporate certain provisions of WIPO ST.26. The “Sequence Listing XML” part of the disclosure may be submitted:

  • as an XML file through the USPTO’s Patent Center electronic filing system (uploading XML files is not supported in EFS-Web); or
  • as an XML file on read-only optical disc(s), as permitted by 37 CFR 1.52(e)(1)(ii) and labeled according to 37 CFR 1.52(e)(5).

5. How does an applicant generate an ST.26-compliant Sequence Listing XML?

WIPO Sequence is a free desktop tool that allows applicants to author and validate sequence information to generate ST.26-compliant sequence listings. The latest version can be downloaded at WIPO Sequence Suite. Check often for updates.