Why 800 numbers are getting their own robocalls

Cellphone users have been deluged by spam calls in recent years, but they’re not the only ones dealing with an onslaught of automated messaging.

Businesses with 1-800-style toll-free lines for sales and customer service have also seen bursts of unwanted calls that can not only tie up their lines but cost them money, since they typically pay the costs of incoming calls, according to the phone analytics company Invoca. But unlike the calls received by individual people, which might be trying to sell shady vacation deals or ensnare victims in scams, many of the calls to toll free numbers simply play bizarre clips of ambient noise or recordings of muffled conversations.

“A customer of ours kind of contacted us like, we’re getting weird phone calls, they don’t make any sense,” says James Brown, a senior manager of infrastructure and security at Invoca. “We don’t know why they’re coming in.”

That’s because the robocallers aren’t looking to make money by selling or stealing anything from the help desks and customer service lines they’re calling, he says. Instead, they’re looking to get a portion of the long distance charges paid by the owners of those toll-free numbers, through complicated multi-party billing systems that pay various companies involved in connecting the calls.

“If my carrier delivers a call, they charge me,” Brown says of the toll-free billing system. “If another carrier delivers it to that carrier, they charge them.”

With modern digital phone systems, it’s easier than ever for small companies to get into the business of interconnecting calls between larger carriers. And because companies can make money by being a part of that chain of connections between callers and toll-free lines, some offer incentives to customers and other carriers for sending 800-number traffic their way.

“Under our current rules, when a robocaller places a call, the carrier it uses will be compensated for originating the call,” Federal Communications Commission Chairman Ajit Pai said in a statement last year. “And if the carrier has done a backroom deal with the robocaller, then the robocaller profits each and every time it makes a call.”

That naturally creates an incentive for fraudsters to drum up bogus traffic, playing whatever sounds it takes to keep operators or automated systems on the line as charges rack up, and not all phone companies work equally hard to keep spam off their network.

“Some of them will pop up and they will attempt to blend this fraudulent traffic into legitimate traffic or at least turn a blind eye to this kind of fraudulent traffic,” Brown says.

In some cases, according to a comment Verizon filed with the FCC about the issue, robocallers even deliberately press the pound sign periodically to cause toll-free services’ menus to loop, keeping them on the line to rack up charges.

“Sometimes, that will have no effect, and the call will soon time out,” according to the filing. “Sometimes, it may prolong the call for another 30 or 60 seconds. But sometimes, periodically hitting the ‘#’ key will send [a toll-free] call into an endless loop, generating minute after minute of originating access charges for the originating local exchange carrier, which has partnered with the caller to share the revenue.”

Once Invoca learned about the problem, it set up a kind of honeypot system with tens of thousands of essentially randomly created toll-free numbers. That let the company gather metadata about spam calls and record them as they came in, letting them gather information that individual phone line owners—who only know what’s coming to their systems—and carriers, who naturally can’t record calls bound for their customers, couldn’t collect on their own.

“The carriers really felt they were hamstrung,” says Brown. “They suspected there was a lot of fraud going on, but they had no way to identify which calls were fraudulent and which were not.”

Invoca helps its customers block bogus calls to their toll-free numbers and absorbs the cost of those that make it through. Brown says the company also shared data with the Federal Bureau of Investigation about the calls.

The FBI declined to comment, citing a policy of not discussing an ongoing investigation. A spokesperson said the FBI doesn’t specifically track toll-free-related call fraud but said anyone receiving scam calls should hang up immediately and report them to law enforcement.

The FCC is also considering ways to address the issue. Last year, the telecom regulator began seeking public comment on a proposal that would shift some of the charges involved in calling toll-free numbers from the called party’s carrier to that of the calling party. It’s won praise from many in the industry—”The FCC’s rulemaking proposals demonstrate it’s serious about curbing arbitrage and fixing the problem,” a Verizon spokesperson told Fast Company in an email—although some have expressed concern the particular changes proposed could lead to unexpected bills for consumers dialing 800 numbers.

“While consumers on unlimited mobile plans may not immediately feel the pinch of this proposal, the rest of us who lack them certainly will,” warned FCC Commissioner Jessica Rosenworcel in a statement last year.

In the meantime, Brown says Invoca is ramping up its use of machine learning to help spot scammers based on data points from its growing set of fraudulent calls.

“We’re actually pretty excited,” he says. “We’re taking our honeypot to a whole new level.”