Patent applications containing DNA, RNA

As from 1 July 2022 all patent applications containing DNA, RNA and protein sequences that are filed in terms of the Patent Cooperation Treaty (PCT) must comply with the World Intellectual Property Organisation’s (WIPO) new ST.26 format in extensible markup language (XML) for sequence listings. Several intellectual property offices will also transition from the previous ST.25 format to the ST.26 format from this date.

WIPO ST.26 format

The ST.26 format seeks to harmonise sequence listing practices among intellectual property offices and requires the mandatory annotation of D-amino acids, branched sequences and nucleotide analogs. WIPO has released a new purpose-built software tool, WIPO Sequence, to aid applicants in preparing ST.26 sequence listings, which are available for download from the WIPO website.

The South African Patents Act and Regulations, however, do not mention sequence listings or specify the format that a sequence listing needs to be filed in. Furthermore, the South African Patent Office has not issued any practice note or directive regarding the implementation of the new ST.26 format.

The current practice in respect of national phase applications filed in South Africa is for the Patent Office to issue the granted patent with a notice to the effect that a sequence listing, where it has been filed and forms part of a complete PCT patent application, will be deemed to have been annexed to the registration certificate in the form that it was published by WIPO or as corrected and/or amended in terms of the Patents Act.

Further, it is our practice to file the sequence listing at the South African Patent Office in PDF, which is the only file type currently supported for filing, to ensure that the sequence listing is on file.

It is expected that the ST.25 format will continue to be accepted in South Africa for PCT applications filed prior to 1 July, in accordance with WIPO’s guidelines. In addition, absent any directive from the Patent Office, a divisional patent application filed after 1 July based on a parent patent application that includes a sequence listing in the ST.25 format will also be allowed to carry over the sequence listing from the parent patent application.

Nevertheless, we recommend that for national phase applications filed in South Africa based on PCT applications filed after 1 July 2022, and for complete applications filed after 1 July 2022, sequence listings be filed in the ST.26 format.