Introduction
Sequence listings are a critical formal and substantive component of many biotechnology patent applications filed with the Russian Patent Office (ROSPATENT). Applications covering DNA, RNA, proteins, peptides, antibodies, microorganisms, genetic constructs and other biotechnology inventions may require detailed disclosure of nucleotide and/or amino-acid sequences. For Russian patent applications filed today, the applicable framework is based principally on WIPO Standard ST.26, which replaced the earlier ST.25 standard for applications filed on or after 1 July 2022. ROSPATENT has incorporated ST.26 into its national patent-document requirements and provides ST.26 materials and supporting resources through its website.
1. When is a sequence listing required?
Under the Russian requirements, a sequence listing is required when the invention disclosure contains nucleotide and/or amino-acid sequences falling within the scope of ST.26.
The Russian requirements specify that the description should provide a detailed disclosure of sequences where they are:
- unbranched nucleotide sequences, or linear portions of branched nucleotide sequences, containing 10 or more specifically defined nucleotides; or
- unbranched amino-acid sequences, or linear portions of branched amino-acid sequences, containing 4 or more specifically defined amino acids.
The same basic thresholds are reflected in ST.26. A sequence with fewer than 10 specifically defined nucleotides or fewer than 4 specifically defined amino acids should not be assigned its own sequence identification number in the listing.
Importantly, the analysis is based on how the sequence is disclosed. A sequence that is merely described in prose may be treated differently from a sequence whose individual residues are expressly enumerated. For example, a reference to positions 90–179 of an existing sequence does not necessarily require creation of a separate SEQ ID if the residues themselves are not enumerated.
2. ST.26 XML is the required format
One of the most important changes from the former ST.25 regime is the move to an XML-based sequence listing.
ROSPATENT’s requirements state that the sequence listing is prepared in accordance with WIPO ST.26 and submitted electronically in XML format, using software capable of checking the formal requirements of the listing.
WIPO provides WIPO Sequence, a free software application specifically designed to create and validate ST.26 sequence listings. WIPO identifies the application as the standard preparation tool for applicants filing national, regional and international applications.
ROSPATENT also publishes ST.26 documentation, including the standard itself, the XML document type definition, sample XML files, controlled vocabulary and explanatory examples.
Practical point
Applicants should not treat the sequence listing as a conventional Word or PDF attachment. The XML file is a structured data document containing standardized fields and sequence information. Preparing it manually is therefore considerably more error-prone than generating and validating it with WIPO Sequence or compatible software.
3. Each sequence receives its own SEQ ID NO.
Every sequence included in the listing must receive an individual identification number.
The Russian requirements specify that sequence numbering begins with 1 and proceeds consecutively using whole numbers. The sequence number used in the listing must correspond to the number used when the sequence is referenced elsewhere in the application, including the description, claims, or drawings.
For example:
SEQ ID NO: 1 — nucleotide sequence
SEQ ID NO: 2 — amino-acid sequence
SEQ ID NO: 3 — nucleotide sequence
The application should then use those identifiers consistently, for example, by referring to a nucleotide sequence as “SEQ ID NO: 1.”
Consistency is particularly important during prosecution. Changing identifiers between the specification, claims, drawings and sequence listing can create unnecessary formal and substantive issues.
4. Sequence information must be linked to the invention
A sequence listing is not a substitute for the substantive disclosure required by the Russian patent rules.
For inventions involving nucleic acids, proteins, polypeptides, or peptides, the Russian requirements call for disclosure that enables the relevant biological material to be understood and used. Depending on the invention, this may include the sequence identifier associated with the relevant biological function, physical or chemical characteristics, the method by which the material was obtained and evidence of its suitability for the stated purpose.
Thus, simply attaching an XML file containing a sequence is not necessarily sufficient. The specification should explain what the sequence represents and how it contributes to the claimed invention.
For example, where a patent concerns a novel protein, the specification may need to establish:
- the protein’s amino-acid sequence;
- the corresponding SEQ ID NO.;
- its biological activity;
- relevant structural or functional characteristics;
- how the protein is produced; and
- experimental data demonstrating the claimed technical effect, where appropriate.
5. Language requirements in a Russian application
ST.26 contains standardized, language-independent terminology and controlled vocabulary. ROSPATENT’s national requirements also impose specific language requirements for information entered into the sequence listing.
According to the Russian rules, language-independent vocabulary used in the listing is presented in accordance with ST.26 and is not translated. At the same time, language-dependent free-text qualifiers must be provided in Russian and English.
There are also specific requirements for identifying the invention and applicant. The invention title in the appropriate sequence-listing field must be in Russian and correspond to the title in the patent specification. An English or other-language version may additionally be supplied.
Similarly, the applicant’s name and the first inventor’s name are entered in Russian in the relevant fields and must correspond to the application. Transliteration or translation into Latin characters is additionally required.
This means that a sequence listing prepared for an international filing should not simply be copied into a Russian national application without checking its bibliographic and language-dependent fields.
6. XML structure and bibliographic data
An ST.26 XML sequence listing contains both general information and sequence-specific information.
ROSPATENT’s requirements describe the XML file as containing:
- a general-information section, identifying the patent application to which the listing relates; and
- a sequence-data section, containing one or more data elements for individual sequences.
The bibliographic information should therefore be checked carefully against the Russian application before filing. Errors in the applicant name, inventor information, application information, or invention title can create formal discrepancies even where the underlying biological sequences are correct.
7. What types of sequences should practitioners pay particular attention to?
Modern biotechnology applications often contain sequence types that were difficult or impossible to represent adequately under the older ST.25 framework. ST.26 was designed in part to accommodate developments such as branched sequences, D-amino acids and nucleotide analogues.
Particular attention may therefore be needed for:
- DNA and genomic sequences;
- RNA sequences;
- coding sequences and open reading frames;
- amino-acid sequences;
- peptides and polypeptides;
- antibody and antibody-fragment sequences;
- variants and mutants;
- fusion proteins;
- modified nucleic acids;
- nucleotide analogues;
- branched sequences; and
- sequences disclosed in examples, claims, figures, or other portions of the application.
A sequence should not be omitted merely because it appears outside the principal “Sequence Listing” section of the specification. The ST.26 analysis considers sequences disclosed elsewhere in the application.
8. Special issues with partial sequences
Partial sequences are a frequent source of confusion.
If an application says, for example, that a construct contains nucleotides 100–250 of SEQ ID NO: 1, that reference does not necessarily require a new SEQ ID for the partial sequence if the residues are not separately enumerated.
Conversely, if the application expressly lists the residues constituting a 151-nucleotide partial sequence, that separately enumerated sequence may fall within the ST.26 requirement and need its own sequence identifier.
Applicants should therefore decide deliberately how sequences and fragments are presented in the specification rather than allowing inconsistent sequence representations to arise during drafting.
9. ST.25 versus ST.26: the transition date matters
The transition from ST.25 to ST.26 occurred on 1 July 2022.
WIPO’s implementation guidance explains that applications filed on or after that date that disclose nucleotide or amino-acid sequences are subject to ST.26. For applications filed before the transition date, the applicable transition rules can preserve ST.25 treatment, including in certain later submissions.
Accordingly, when entering the Russian national phase or prosecuting an older Russian application, practitioners should determine the relevant filing date, rather than automatically converting every historical sequence listing to ST.26.
10. Validation before filing
Validation should be treated as a mandatory quality-control step.
The WIPO Sequence software is designed to check the form of an ST.26 sequence listing and ROSPATENT’s requirements expressly contemplate the use of software that verifies the listing.
Before filing, practitioners should verify at least the following:
- the listing is in XML format;
- every required sequence has been identified;
- the minimum-length rules have been correctly applied;
- SEQ ID numbers are consecutive;
- every SEQ ID is consistent throughout the specification and claims;
- nucleotide and amino-acid characters comply with ST.26;
- qualifiers have been entered correctly;
- Russian and English free-text requirements have been satisfied;
- the invention title matches the Russian application;
- applicant and inventor information matches the application;
- the XML validates successfully; and
- the final XML corresponds exactly to the sequences disclosed in the filed application.
11. Sequence listings and amendments
A particularly important prosecution issue is the relationship between the sequence listing and the substantive disclosure.
Applicants should avoid making changes to a sequence merely to correct a formal inconsistency unless the legal consequences of the change have been considered. Adding or modifying sequence information after filing can raise questions concerning whether the amended subject matter is supported by the original disclosure.
The safest approach is to finalize the biological sequence data before filing and conduct a cross-document comparison between:
- the sequence listing;
- the description;
- the claims;
- the drawings;
- examples; and
- any priority or international application from which the Russian application derives.
12. Practical checklist for Russian biotech patent filings
A robust Russian filing workflow can be organized as follows:
Step 1 — Identify all sequences.
Search the entire application for enumerated nucleotide and amino-acid sequences, including sequences appearing in examples, claims, figures and tables.
Step 2 — Apply the ST.26 inclusion criteria.
Determine which sequences meet the relevant minimum-length and residue-definition requirements.
Step 3 — Assign SEQ IDs.
Number the sequences consecutively and use the same identifiers throughout the patent application.
Step 4 — Build the XML listing.
Prepare the listing using WIPO Sequence or other ST.26-compatible software.
Step 5 — Check national fields.
Verify Russian-language bibliographic information and the required Russian/English treatment of language-dependent text.
Step 6 — Validate.
Run the XML through the applicable validation tools and resolve errors before filing.
Step 7 — Cross-check the application.
Confirm that every sequence referenced in the specification and claims corresponds to the correct SEQ ID and sequence in the XML.
Step 8 — Preserve the filing version.
Keep an exact copy of the XML sequence listing that was submitted with the application, together with the application documents and validation results.
Conclusion
For biotechnology patent applications in Russia, sequence-listing compliance is now fundamentally an ST.26/XML exercise. Since 1 July 2022, the transition from ST.25 has aligned Russian practice with the international ST.26 framework, while ROSPATENT’s national requirements add important details concerning Russian-language bibliographic information, bilingual free-text qualifiers and the relationship between the sequence listing and the patent specification. The key practical lesson is that sequence-listing preparation should begin during patent drafting rather than immediately before filing. A properly prepared ST.26 listing should be generated and validated electronically, while the patent specification and claims should be checked against the final SEQ ID numbering and sequence data. Because Russian patent formalities can change, applicants should verify the requirements applicable on the actual filing date and consult the current ROSPATENT documentation and ST.26 materials. ROSPATENT currently publishes the ST.26 standard and its supporting annexes, while WIPO provides the broader ST.26 resources and WIPO Sequence software.