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WIPO Sequence Software: A Step-by-Step Guide for Patent Preparers

Prelude

WIPO Sequence is the free, WIPO-developed software that creates ST.26-compliant XML sequence listings for patent applications. Since January 2022, ST.26 replaced the old plain-text ST.25 format across all PCT filings and most national offices – including the USPTO and EPO.

If you prepare patent applications disclosing nucleotide or amino acid sequences, WIPO Sequence is not optional. It is the tool. Getting it wrong means a non-compliant listing, a formal objection and a filing date you may not be able to recover.

This guide walks you through the entire process – installation to validated, submission-ready file – in plain, actionable steps.

Before You Start: What You Need

The software: Download WIPO Sequence directly from WIPO’s official site at wipo.int/standards/en/sequence. Always use the latest version – WIPO issues updates that fix validation bugs and add functionality.
System requirements: Windows 10/11, macOS 10.14+, or Linux. Java Runtime Environment (JRE) 11 or higher is required. If the software won’t launch, a missing or outdated JRE is almost always the cause.
Your source data: Have sequences ready in a clean, verified format before opening the software. FASTA files are the fastest input. Raw sequences copied from a specification or lab notebook also work – but verify them against the actual sequence data before you begin. Errors introduced at input cannot be caught by the validator.
The patent specification: You need the specification open alongside the software. Every SEQ ID NO you assign must match exactly how sequences are referenced in the claims and detailed description. This cross-reference is your legal obligation – not just a formatting task.

Step 1: Install and Launch

Download the installer for your operating system and run it. The installation is straightforward – accept the defaults unless your organization has a specific installation directory requirement.

On first launch, WIPO Sequence opens to a blank project screen. Take two minutes to navigate the interface before starting work. The main panels are: Sequence List (left), Sequence Detail (center/right) and Validation Panel (bottom). You will live in all three.

Set your preferences first. Go to File → Preferences and confirm the default organism name format and qualifier settings match your typical filing requirements. These preferences save time across all future projects.

Step 2: Create a New Project

Go to File → New. You will be prompted to enter the general information that forms the listing’s header:

Applicant name – enter exactly as it will appear on the application.

Invention title – copy directly from the patent application title. Character-for-character accuracy here prevents discrepancies between the listing and the application.

Application number – enter if known (national stage or continuation filings); leave blank for new PCT filings where the number is not yet assigned.

Filing date – enter the actual or intended filing date.

Earliest priority date – enter if claiming priority; this affects sequence disclosure compliance assessment.

Software version – WIPO Sequence populates this automatically. Do not edit it.

Save the project immediately: File → Save As. Use a descriptive file name that includes the applicant name, application reference and date. WIPO Sequence saves projects in its own .wipo format – this is your working file. The final output will be exported as XML.

Step 3: Add Sequences

This is the core of the work. For each sequence in the application, you will create one entry in the sequence list.

Adding a sequence: Click the “+” button in the Sequence List panel or go to Edit → Add Sequence.

For each sequence, you must complete the following fields:

Sequence ID (SEQ ID NO): Assigned automatically in order. WIPO Sequence numbers entries sequentially – do not manually change the order once entries are created, as this renumbers downstream sequences and can create SEQ ID NO mismatches with the specification. Plan your entry order before you start adding sequences.

Sequence type: Select from:

DNA – deoxyribonucleotide sequence
RNA – ribonucleotide sequence
AA – amino acid sequence
DNA/RNA – chimeric sequences

Sequence length: Calculated automatically when you enter the sequence. Verify it matches the length as described in the specification.

Organism: Enter the scientific name of the source organism. WIPO Sequence cross-references organism names against a controlled vocabulary list – if the name you enter doesn’t match, you will get a validation warning. Use the lookup function (the magnifying glass icon next to the Organism field) to find the correct form. For synthetic sequences, select “Artificial Sequence” from the dropdown.

Sequence data entry: Paste or type the sequence directly into the sequence input field. WIPO Sequence accepts standard IUPAC nucleotide and amino acid codes. It automatically flags unrecognized characters – review every flag before proceeding.

Critical: If entering sequences from a FASTA file, use File → Import → FASTA to import multiple sequences at once. This dramatically reduces manual entry errors on large listings. After import, verify every sequence against source data – automated import does not guarantee biological accuracy.

Step 4: Add Feature Annotations

This is where ST.26 diverges sharply from the old ST.25 format – and where most errors occur.

ST.26 requires structured feature annotations for biologically meaningful elements within sequences. These are not optional enhancements. For most sequences in a well-drafted patent application, features are mandatory.

To add a feature: Select a sequence in the Sequence List, then click “Add Feature” in the Feature panel.

Required fields for each feature:

Feature key: Select from the controlled vocabulary dropdown. Common keys include:

CDS – coding sequence
sig_peptide – signal peptide
mat_peptide – mature peptide
misc_feature – miscellaneous feature when no specific key applies
V_region, C_region – for antibody variable and constant regions
modified_AA – for non-standard amino acid residues

Location: Enter the start and end positions of the feature within the sequence (e.g., 1..750 for a CDS spanning positions 1 to 750). For complement strand features, use the complement() notation.

Qualifiers: Each feature key requires specific qualifiers. For a CDS, the /product qualifier naming the encoded protein is mandatory. For misc_feature, a /note qualifier describing the feature is required. WIPO Sequence will flag missing mandatory qualifiers during validation.

Antibody sequences: For monoclonal antibody applications, annotate each CDR region, framework region, signal peptide and constant domain with the appropriate feature key and qualifiers. This is the most annotation-dense work you will do in WIPO Sequence – plan the time accordingly.

Step 5: Add Free Text Qualifiers

Many annotations require free text qualifiers – plain-language descriptions that explain the biological significance of a feature. These must be:

Accurate – consistent with the description in the specification
Concise – not duplicating large amounts of specification text
ST.26 compliant – certain qualifier types have specific format rules; review WIPO’s ST.26 Annex I for the controlled vocabulary of acceptable qualifier names

Common free text qualifiers include /note, /product, /protein_id and /gene. Enter these in the Qualifier panel for each feature.

Consistency between free text qualifiers and the specification is a legal requirement, not a style preference. If the specification describes a protein as “interleukin-6 receptor binding domain,” your /product qualifier should match that description – not introduce a new term.

Step 6: Validate the Listing

When all sequences and features are entered, run the validator before doing anything else.

Go to Tools → Validate or click the Validate button in the toolbar.

WIPO Sequence runs two levels of validation:

Structural validation checks XML compliance: required fields present, controlled vocabulary used correctly, file format integrity. Structural errors are show-stoppers – they must be resolved before export.

Semantic validation checks biological logic: feature locations within sequence bounds, consistent use of qualifier types, organism name recognition, sequence type consistency. Semantic warnings may not prevent export but often indicate genuine errors.

Reading the validation report:

The Validation Panel at the bottom of the screen shows errors (red) and warnings (yellow). Click on any item to jump directly to the relevant sequence or feature.

Work through every red error first – resolve each one before moving to warnings. Common errors include:

Missing mandatory qualifier – a feature key requires a qualifier you haven’t added
Location out of bounds – feature location extends beyond the sequence length
Unrecognized organism name – organism not in controlled vocabulary; use the lookup
Invalid sequence character – a character in the sequence data that is not a valid IUPAC code

Do not export a listing that has unresolved red errors. The USPTO and EPO validators will catch the same errors and reject the file.

For yellow warnings: review each one. Some are genuine errors disguised as warnings; others reflect legitimate edge cases. Document your reasoning for any warning you choose not to resolve.

Step 7: The SEQ ID NO Audit

Before exporting, perform the single most important legal verification in the entire process.

Open the patent specification alongside WIPO Sequence. For every SEQ ID NO in the application:

Confirm the sequence appears in WIPO Sequence with that exact SEQ ID NO
Confirm the sequence type (DNA, AA, etc.) matches how it is described in the specification
Confirm the sequence length matches any length statement in the specification
Confirm the organism matches the specification’s description of the source

Then reverse it: for every sequence in WIPO Sequence, confirm it is referenced at least once in the specification or claims.

A SEQ ID NO that exists in the listing but is never referenced in the specification is a red flag. It may indicate an error in the listing or a gap in the specification. Resolve it before filing.

A sequence referenced in the specification that is absent from the listing is a filing defect. Depending on when it is discovered, correcting it may require a petition or amendment. Catch it here.

Step 8: Export the XML File

When validation is clean and the SEQ ID NO audit is complete, export the final listing.

Go to File → Export → ST.26 XML.

WIPO Sequence will prompt you to confirm the file save location. Save to a designated output folder – not your desktop, not a temp folder. The exported file will have the .xml extension.

After export, do not open the XML file in a text editor and manually edit it. Any manual modification invalidates the ST.26 compliance of the file. If you need to change anything, return to the WIPO Sequence project file, make the change, re-validate and re-export.

File naming: Follow the naming convention required by your target office:

USPTO: the file should be named according to Patent Center’s upload requirements; check current USPTO guidance before filing
EPO (OLF): follow EPO’s specific naming convention

PCT (ePCT): follow WIPO’s ePCT upload specifications

Step 9: Run the Final Validator Check

Before submitting to any patent office, run the exported XML file through the standalone WIPO Sequence validator – available at the same download page as the main software.

This step is separate from the in-application validation in Step 6. The standalone validator confirms that the exported XML file itself is compliant as a standalone document – not just that your project data was valid.

For USPTO filings, additionally validate through the Patent Center pre-submission checker before finalizing your filing package. The USPTO validator catches office-specific requirements beyond the base ST.26 standard.

If either validator returns errors on the exported XML: do not file. Return to the project file, identify and fix the source of the error and re-export and re-validate.

Step 10: File and Confirm

Submit the validated XML file through the appropriate filing platform:

USPTO: Patent Center – upload as “Sequence Listing XML”
EPO: Online Filing (OLF) – upload as the ST.26 XML component
PCT: ePCT – upload as the sequence listing component in the application package

After filing, immediately download and retain the filing receipt. Confirm that the sequence listing file is listed as received in the filing confirmation. A missing or corrupted sequence listing at filing can affect your filing date for sequence-dependent claims.

Five Mistakes That Cause the Most Problems

Entering sequences in the wrong order SEQ ID NOs are assigned sequentially by entry order. If you add sequences out of the order they appear in the specification, you will have to renumber – which means updating the specification too. Plan the entry order before you start.
Skipping feature annotations Thinking you can file without features to save time is a false economy. Examiners require them; offices will object. Annotate correctly the first time.
Editing the exported XML manually Never. If it needs a change, fix it in the project file and re-export.
Filing the .wipo project file instead of the .xml export The project file is your working document. The XML export is the submission document. They are not interchangeable.

5. Ignoring validation warnings Yellow warnings are not clearances. Review every one. Some are genuine biological errors that will be caught by an examiner even if the automated validator lets them pass.

Conclusion

WIPO Sequence is powerful, well-documented and free. The learning curve is real but short. Most preparers are fully proficient after two or three complete listings.

What the software cannot do is verify biological accuracy, ensure legal consistency with the specification, or substitute for the judgment of someone who understands both the science and the patent law. That combination – WIPO Sequence’s technical precision plus the preparer’s legal and scientific knowledge – is what makes a submission-ready, legally defensible sequence listing.

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At our Sequence Listing Company, we specialize exclusively in creating perfect patent sequence listings for biotechnology and pharmaceutical companies. Founded by patent attorneys and bioinformatics specialists with over 10 years of experience, we understand the critical intersection of scientific innovation and intellectual property protection. Our dedicated team has helped hundreds of companies successfully navigate the complex regulatory requirements of sequence listings across global patent offices. We combine technical precision with regulatory expertise to ensure your valuable innovations receive the protection they deserve without delays or complications.

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