Under PCT Rule 5.2(a), the sequence listing must always be presented as a separate part of the description. When filing an international application (PCT) using EFS-Web, the sequence listing part of the description may be submitted either as a single ASCII text file with a “.txt” extension (e.g., “seqlist.txt”) or as a PDF file. Note that 100 megabytes is the size limit for submitting a sequence listing text file via EFS-Web. If the sequence listing is submitted as an ASCII text file, applicant need not and should not submit any additional copies.