Background Nucleotide and/Or Amino Acid Sequence Listings

Date Published

Nucleotide and/or amino acid sequence listings are representations of the sequence in a standardised format set down in Annex C of the Administrative Instructions under the Patent Cooperation Treaty.  This listing(s) may be supplied with an international application in addition to the sequence disclosed in the specification.

Note: A sequence listing is a separate part of the description that is presented in a specific format (Annex C).  Nucleotide or amino acid sequences that appear in the figures or drawings, or in the text of the description, do not constitute a sequence listing.

The listing may be filed as part of the specification or it can be furnished separately at a later date.  Where the sequence listing was originally filed as part of the description or where it was filed in response to an Article 14 objection (certain defects in the specification) by the Receiving Office, the sequence listing forms part of the description (Rule 5.2) and hence forms part of the pamphlet.  If however the sequence listing is only filed in response to a Rule 13ter request by the ISA then the sequence listing does not form part of the description (unless the subject of an Article 34 amendment) and will not be part of the pamphlet (Rule 13ter (f)).

Examiners should note that the expressions "nucleotide sequence" and "amino acid sequence" are defined to mean an unbranched sequence of ten or more contiguous nucleotides and an unbranched sequence of four or more contiguous amino acids, respectively; branched sequences are specifically excluded (Annex C).

Where the international application contains a disclosure of a nucleotide and/or amino acid sequence, the sequence listing may be in paper form, or electronic form on a (ISO9660) CD-ROM, CD-R or DVD.  According to section 208 of the Administrative Instructions, the standard prescribed for a sequence listing is that specified in Annex C. [Rule 5.2 Ad. Inst. 208 Ad. Inst. 801]

As of 1 July 2009, the filing of 'mixed mode' PCT applications, i.e. international applications where the sequence listing is filed in electronic form and the remainder of the international application is filed in paper form, is not permitted.  Thus international applications must be filed in either paper or electronic form in order to be accepted by the Receiving Office.  

When an international application containing a sequence listing is lodged with the Receiving Office, PCT unit will check that the necessary formalities requirements have been met before the application is forwarded to the relevant examination section.

Note: An application where the sequence listing is provided in paper form, may also contain a copy of the sequence listing in electronic form in order to comply with Rule 13ter [Ad. Inst. 208 Ad. Inst. at Annex C] (see below)

If the sequence listing provided at filing is not in electronic form, or if one is provided which does not comply with Annex C, the ISA, under Rule 13ter.1(a), may issue an invitation to the applicant to furnish a sequence listing in electronic form, or to furnish a listing which complies with Annex C.  The sequence listing provided must be in electronic form encoded as a text file on CD or DVD media.  The prescribed time for responding to such an invitation is usually one month.  (PCT/ISA/225) [Rule 13ter.1(a) Ad. Inst. 513(a)]

If the applicant does not comply with an invitation, the ISA will only search the international application to the extent that a meaningful search can be carried out without the sequence listing. [Rule 13ter.1(c)]

Any limitations placed upon the scope of the search, as a result of non-compliance with this request, should be discussed by the three person team.