Sirius XM's online FCC public inspection file is available here.

Persons having questions about Sirius XM's FCC online public inspection file, or persons with disabilities who need assistance relating to the content of that file, should send an email to publicfilequestions@siriusxm.com. Questions or concerns relating to the accessibility of the FCC's online public file system should be directed to the FCC's Consumer Center at 888-225-5322, 888-835-5322 (TTY), or fccinfo@fcc.gov.

Sirius XM also maintains a back-up political file here. That file will be made available to the public in the event Sirius XM becomes aware that the FCC's online public inspection file is unavailable.