Just when you think you can get a handle on something (like robocalls), you find out it’s pretty much a lost cause. According to Considerable.com’s Sathvik Prasad and Bradley Reaves, more than 80% of robocalls come from fake numbers. That means that either answering or ignoring these calls has no effect on how many more you’ll get.
In an 11-month study from February 2019 to January 2020 monitoring unsolicited (unwanted) phone calls, Prasad and Reaves monitored every phone call received to over 66,000 phone lines in the Robocall Observatory at North Carolina State University. They report, “We received 1.48 million unsolicited phone calls over the course of the study. Some of these calls we answered, while others we let ring. Contrary to popular wisdom, we found that answering calls makes no difference in the number of robocalls received by a phone number. The weekly volume of robocalls remained constant throughout the study.”
As part of their study, they also developed the first method to identify robocalling campaigns responsible for a large number of these annoying, illegal and fraudulent calls. They identified a pattern of calls of three main types: (1) smattering of calls about student loans, health insurance, and Google business listings, (2) general financial fraud, and (3) a long-running Social Security scam.
Their findings? More than 80% of calls from an average robocalling campaign use fake or short-lived phone numbers to place their unwanted calls. “Using these phone numbers, perpetrators deceive their victims and make it much more difficult to identify and prosecute unlawful robocallers,” they said.
They also saw that some fraudulent robocalling operations impersonated government agencies for many months and without detection. “They used messages in English and Mandarin and threatened the victims with dire consequences. These messages target vulnerable populations, including immigrants and seniors.”
The conventional way providers identify the true source of a call uses a time-consuming, manual process called “traceback.” But with the number of robocalls proliferating today, there are too many robocalls for traceback to be a practical solution for every call. So Prasad and Reaves are developing a system for robocalling campaign identification that can be used by service providers to identify large-scale robocalling operations.
“Using our methods, providers need to investigate only a small number of calls for each robocalling campaign. By targeting the source of abusive robocalls, service providers can block or shut down these operations and protect their subscribers from scams and unlawful telemarketing,” they explain.
Prasad and Reaves say no one knows how robocall scammers interact with their victims and how often they change their strategies, including those now posing as concerned individuals using Covid-19 as a premise to defraud people. But the two will continue their research on robocalls to see what can be done to reduce them. “We’re also developing techniques to better identify, understand, and help providers and law enforcement target robocalling operations,” they said.
