Why does the USPTO transform Sequence Listing XML into ASCII text?

This page is an FAQ based on guidance from the Manual of Patent Examining Procedure. It is provided as guidance, with links to the ground truth sources. This is information only: it is not legal advice.

The USPTO transforms Sequence Listing XML into ASCII text to improve readability for publication purposes. According to MPEP 2419: “Because a ‘Sequence Listing XML’ exists only in .xml file format, the USPTO uses a style sheet to transform the ‘Sequence Listing XML’ into an ASCII text file which will be used for printing purposes to present the sequence information in a format that is more easily read.” This transformation ensures that the sequence information is presented in a user-friendly format in published patent documents.