AT&T falsely reported to the Federal Communications Commission that it offers broadband in nearly 3,600 census blocks spread across parts of 20 states.

AT&T disclosed the error to the FCC in a filing a week ago. The filing provides "a list of census blocks AT&T previously reported as having broadband deployment at speeds of at least 25Mbps downstream/3 Mbps upstream that AT&T has removed from its Form 477 reports." The 78-page list includes nearly 3,600 blocks.

With Form 477 reports, ISPs are required to tell the FCC which census blocks they offer service in. The FCC uses the data to track broadband-deployment progress and, crucially, to decide which census blocks get government funding for deploying Internet service. AT&T falsely reporting broadband-data coverage could prevent other ISPs from getting that funding and leave Americans without broadband access.

When contacted by Ars, AT&T said the mistake was caused by a software problem. "The updates to the census blocks address an issue with a third party's geocoding software. There has been no change to our service area and this doesn't affect the service we provide our customers," AT&T told Ars.

Error “unnoticed for 2-plus years”

The error appeared in AT&T filings to the FCC going back to December 2017, broadband researcher Derek Turner told Ars. Turner is the research director of consumer-advocacy group Free Press.

The error affecting 3,600 census blocks is relatively small, as AT&T offers service in 2.2 million blocks, Turner said. But aside from one even bigger error by an ISP called BarrierFree last year, Turner said he hasn't "seen any other ISP reporting error like this before" and that "it is curious that the [AT&T] error may have gone unnoticed for 2-plus years."

There are more than 11 million census blocks in the US, though about 5 million are entirely unoccupied. "While relatively small errors like this don't end up changing conclusions about national trends, it certainly can impact the FCC decisions about where to spend—and where to not spend—scarce subsidy funds," Turner said. "AT&T should be quite a bit more forthcoming about the exact nature of this error and how it discovered it, so that other ISPs can be sure they're not making similar errors."

We asked the FCC if it plans to punish AT&T or at least investigate the rest of its Form 477 filings to make sure they are accurate, and we will update this article if we get a response.

The FCC recently found that Verizon, T-Mobile, and US Cellular exaggerated their 4G cellular coverage in official filings. But the carriers faced no punishment even though the FCC said it would issue an advisory to industry members reminding them "of the penalties associated with filings that violate federal law."

AT&T offers wireline service in 21 states, and the mistake affected certain census blocks in all of those states except Nevada. The states where AT&T falsely reported coverage in some census blocks are Alabama, Arkansas, California, Florida, Georgia, Illinois, Indiana, Kansas, Kentucky, Louisiana, Michigan, Missouri, Mississippi, North Carolina, Ohio, Oklahoma, South Carolina, Tennessee, Texas, and Wisconsin.

FCC to issue $16B before getting more accurate data

AT&T discovered its error after the FCC asked carriers to update their Form 477 filings in preparation for Phase 1 of the commission's $20.4 billion Rural Digital Opportunity Fund (RDOF). The FCC is targeting Phase 1 funding of up to $16 billion at census blocks where there isn't any 25/3Mbps home-Internet service. The program is paid for by Americans through fees imposed on phone bills.

In its FCC filing, AT&T noted that the 3,600 census blocks "may be eligible for the RDOF Phase I auction" if no other ISPs report offering 25/3Mbps broadband in the blocks. If AT&T hadn't found the error, none of the 3,600 blocks would have been considered for funding in the auction.

The FCC has long known that its Form 477 system is inaccurate because it counts entire census blocks as served if an ISP offers service to just one home in a block. The FCC in August 2019 finally ordered ISPs to submit geospatial maps of where they provide service instead of merely reporting which census blocks they offer service in.

But the FCC is proceeding with the RDOF auction in October before getting the new, more accurate data. Chairman Ajit Pai resisted calls from Democratic Commissioners Jessica Rosenworcel and Geoffrey Starks to delay the first auction until data based on geospatial maps is available.

Reader without wired broadband flagged AT&T filing

We didn't notice the AT&T filing until a reader named Jonathan Meyer pointed it out to us. Meyer lives in a rural part of Indiana in Bartholomew County and said he has been following the RDOF process closely because he can't get modern broadband service at his house.

"AT&T received a subsidy under the original CAF [Connect America Fund, the RDOF predecessor] program to provide DSL service in our area," Meyer told Ars. "However, by the time that we built our home on the property, they claimed that they had met their coverage obligations and are no longer serving new customers."

Meyer said he is "shocked that a company like AT&T would have so many errors and I'll bet that those errors had been routinely repeated for quite some time."

Because he lacks wired-broadband access, Meyer uses a Verizon residential service that connects to the cellular network and comes with an onerous data cap and overage fees. "Other than being very expensive if we go over our 40GB monthly cap, the service has ranged from decent three years ago to pretty good after Verizon built two new towers nearby. However, an average of $190 per month for service that averages 3 to 5Mbps makes me very anxious for a fiber or coax option," he said.

John Bergmayer, legal director of consumer-advocacy group Public Knowledge, called AT&T's Form 477 error "another example of how poor our broadband data-collection practices are in general.

"It's hard to craft good policy without good data, and it's frustrating to waste time arguing about data collection, mapping, and similar subjects, instead of what to do about actual broadband deployment and availability," Bergmayer said.