So, did any customers of the unknown carrier notice an outage?

As several people pointed out, there was also an earlier confidential outage report on August 2 2001. The FCC website has been updated, and the previously "hidden" carrier name for both confidential outages appears to be Sprint. But the reports are still confidential. http://www.fcc.gov/Bureaus/Engineering_Technology/Filings/Network_Outage/200... http://www.fcc.gov/Bureaus/Engineering_Technology/Filings/Network_Outage/200... Customers noticed several minor outages on October 20. But I couldn't figure out why Sprint would require confidential treatment for any of them. The confidential report back in August seems to indicate whatever the reason for confidentiality, it has nothing to do with post-September 11 environment.