MPEP § 2412.05(a)
[Editor Note: This section is applicable to all applications with a filing date, or, for national phase applications, an international filing date, on or after July 1, 2022, having disclosure of one or more nucleotide and/or amino acid sequences as defined in 37 CFR 1.831(b). Formatting representations of XML (eXtensible Markup Language) elements in this section appear different than shown in Standard ST.26, which may be accessed at: www.wipo.int /export/sites/www/standards/en/pdf/03-26-01.pdf.]
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In accordance with 37 CFR 1.832(a), the sequence identifiers in the "Sequence Listing XML" must begin with 1 and increase sequentially by integers. The requirement for sequence identifiers, at a minimum, requires that each sequence be assigned a different number for purposes of identification. However, where practical and for ease of reference, sequences should be presented in the "Sequence Listing XML" in numerical order and in the order in which they are discussed in the application.
Each nucleotide and/or amino acid sequence that meets the definition in 37 CFR 1.831(b) and is enumerated by its residues must be assigned a separate sequence identifier, including a sequence which is identical to a region of a longer sequence. See MPEP § 2412.02 for further description of a "sequence".
Where no sequence is present for a sequence identifier, i.e. an intentionally skipped sequence, "000" must be used in place of a sequence in a "Sequence Listing XML". The total number of sequences indicated in the "Sequence Listing XML" must equal the total number of sequence identifiers, whether followed by a sequence or by "000".
WIPO Standard ST.26 paragraphs 58 and 59 require that an intentionally skipped sequences in a "Sequence Listing XML" must be represented as follows: