Biotechnology patent applications occupy a unique corner of prosecution practice: the applicant’s own disclosure typically includes a formal sequence listing – a structured file of nucleotide and/or amino acid sequences that supports the claims – and much of the relevant prior art in the field consists of sequence data too, published in databases like GenBank, UniProt, or in earlier patent filings. That overlap creates a specific and under-discussed practice area: how a third party can use sequence-containing prior art to challenge or narrow a pending competitor’s biotech application before it issues and what happens when the sequence data itself is at the center of the dispute.
This guide covers both halves of that intersection – the mechanics of third-party preissuance submissions and the sequence-listing-specific issues that make biotech submissions different from a typical prior-art challenge.
1. The Vehicle: Third-Party Preissuance Submissions
The primary tool available to a third party who wants to put prior art in front of an examiner – without becoming a party to the case – is the preissuance submission created by the America Invents Act, codified at 35 U.S.C. § 122(e) and implemented at 37 CFR § 1.290.
What it allows
A third party may submit patents, published patent applications, or other printed publications of potential relevance to a pending, published application, along with a concise statement of relevance for each item. The examiner is not obligated to discuss or rely on the submission, but compliant submissions are entered into the file and considered.
What it does not allow
- No arguments about patentability (obviousness, anticipation, etc.) may be made – only a “concise description of the asserted relevance” of each document, tying it to specific claim language or disclosure.
- The submitting party cannot participate further; there’s no right of reply if the examiner disagrees and no estoppel is created either way.
- Submissions are limited to prior art documents and publications – not declarations, expert opinions, or other evidentiary material a party could offer in litigation or in an inter partes proceeding.
Timing window
A submission must be filed by the later of (1) six months after the application is first published, or (2) the date of the first office action rejecting any claim on the merits – and in all cases before a notice of allowance issues. This window is tight and unforgiving: once a notice of allowance is mailed, the door closes, regardless of what prior art later surfaces.
Scope of applications covered
Submissions may be made in any pending, non-provisional utility, design, or plant application (including continuations), whether published or not. They are not available for provisional applications, issued patents, reissue applications, or reexamination proceedings – those require different post-grant mechanisms (ex parte reexamination, inter partes review, post-grant review).
Anonymity and identification requirements
A submission does not have to disclose the real party in interest by name – many are filed anonymously or through counsel – but it must comply with formal requirements: a document list on the required USPTO form, copies of each non-patent publication and a certification that the submitting party doesn’t have a duty of disclosure to the application under 37 CFR 1.56 (i.e., isn’t an inventor or someone otherwise obligated to be candid with the office on that specific application).
2. Why Sequence Data Makes This Harder
Ordinary prior-art submissions point an examiner to a passage of text. Sequence-based submissions have to point an examiner to a specific alignment or identity relationship between strings of nucleotides or amino acids – and that creates several practice-specific complications.
A. The prior art itself may be a database entry, not a “publication” in the traditional sense
GenBank, UniProt and similar repositories are continuously updated, versioned and sometimes revised or withdrawn. A third party relying on a database sequence as prior art needs to:
- Capture and preserve the specific version/accession date relied upon, since the same accession number can point to different sequence data at different points in time
- Be prepared to establish the publication date of that version – the priority date comparison depends on when that specific sequence entry became publicly accessible, not just when the accession number was first created
- Submit archived or dated printouts, since a live database record is a moving target that can change or disappear before the examiner reviews it
B. Sequence identity and alignment isn’t self-evident from the document alone
A concise description of relevance for a sequence-based submission typically needs to identify:
- Which SEQ ID NO(s) in the applicant’s own sequence listing correspond to the prior art sequence
- The percent identity or specific alignment between the submitted sequence and the claimed sequence, since biotech claims are frequently drafted around percent-identity thresholds (e.g., “at least 95% identical to SEQ ID NO: 1”)
- Whether the identity is over the full length of the claimed sequence or only a fragment – partial-length matches are a common and legitimate point of dispute
Because the statute prohibits arguments about patentability, this description has to walk a careful line: stating the alignment as a fact (a description of what the documents show) rather than arguing that the alignment renders the claim obvious or anticipated.
C. Format mismatches between older and newer sequence listings
Since WIPO Standard ST.26 replaced the older ST.25 format for filings on or after July 1, 2022, a third party working with pre-2022 prior art (formatted under 37 CFR §§ 1.821–1.825, ST.25) may need to cross-reference it against an applicant’s newer ST.26-format sequence listing (37 CFR §§ 1.831–1.835), which uses a different XML structure, expanded feature annotations and different rules on what qualifies as a disclosed sequence (for example, ST.26 excludes very short sequences below defined nucleotide/amino-acid length thresholds that were sometimes listed under ST.25). Confirming that a SEQ ID NO in an older reference and a SEQ ID NO in the newer application actually refer to comparable subject matter is a necessary, often overlooked step.
D. Sequence variants and functional fragments
Biotech prior art frequently discloses a “parent” sequence with related variants, mutants, or fragments described elsewhere in the same document (in text, examples, or supplementary tables) rather than as a separately numbered sequence entry. A submission needs to make clear where in the reference the relevant variant appears, since sequence listings only capture the raw sequence itself – not always the surrounding disclosure explaining a variant’s function or the applicant’s basis for claiming a range of identity around it.
3. Practical Workflow for a Third-Party Sequence-Based Submission
- Monitor the target application. Publication alerts (through Patent Center or commercial docketing/watch services) are essential, since the six-month-from-publication deadline runs regardless of when the third party becomes aware of the application.
- Identify and lock down the sequence prior art. Pull the specific database version or publication, note its public-availability date and preserve a dated copy – don’t rely on a live link that could change.
- Run the alignment. Use standard bioinformatics alignment tools to establish percent identity between the prior art sequence and the claimed sequence(s) and document the alignment output as part of the supporting record (even though it can’t be submitted as argument, having it prepared supports an accurate factual description).
- Draft the concise description of relevance as a factual statement. State what the reference discloses and how it maps onto specific claim language or specific SEQ ID NOs, without characterizing that overlap as invalidating.
- Confirm eligibility requirements. Verify the application is still within the submission window, is a covered application type and that the submitting party doesn’t have a 37 CFR 1.56 duty of disclosure to that specific application.
- File through Patent Center using the dedicated third-party preissuance submission interface, attaching the required document list form and copies of each non-patent publication relied upon.
- Track the outcome, but expect silence. Because prosecution remains ex parte, there’s no right to know how the examiner treated the submission beyond what appears on the record – if the examiner doesn’t cite the reference on a Notice of References Cited or discuss it in an office action, consideration cannot be presumed.
4. Strategic Considerations
- This is a narrowing tool, not a blocking tool. A well-supported sequence-based submission can prompt a rejection or force narrower claim amendments, but it cannot stop allowance outright the way an opposition proceeding might in other jurisdictions – the U.S. system doesn’t have pre-grant opposition.
- Quality over quantity. Because arguments aren’t permitted, the submission lives or dies on how clearly the concise description ties a specific sequence match to specific claim language. A vague or poorly mapped submission is likely to be set aside without real engagement, since examiners aren’t required to independently reconstruct the alignment analysis.
- Consider downstream use. A submission that becomes part of the file wrapper – and later appears on the face of an issued patent, if the application proceeds to grant – can be useful later in litigation for claim construction or prosecution history purposes, even if it didn’t change the outcome during examination.
- Weigh this against post-grant alternatives. If the sequence prior art is strong enough to potentially invalidate claims outright and the six-month/first-action window has closed or is about to, post-grant tools such as inter partes review may ultimately be a more effective (if more expensive) venue, since they allow full argument and expert evidence that a preissuance submission does not.
Key Takeaway
Third-party preissuance submissions give competitors, research institutions and other interested parties a low-cost way to put sequence-based prior art in front of an examiner before a biotech patent issues – but the mechanism’s formal limits (no argument, tight timing, ex parte silence) combine with the technical demands of sequence comparison (versioned database records, identity/alignment mapping, ST.25-to-ST.26 format differences) to make this a submission type where precision in the concise description of relevance matters more than volume of prior art submitted.