Anyone who has tried to enjoy their dinner in peace without being constantly disturbed by robocalls will be thrilled to know that a man named Aaron Foss has figured out a way to block robocalls for good. In 2013, the Federal Trade Commission held their first Robocall Challenge, which was a contest to see who could build the most effective robocall blocker. Out of 800 submissions, Foss shared the first place prize, winning $25,000.

Nomorobo works by routing calls through a service that checks the number against a whitelist of legitimate numbers and then a blacklist of known spammers, yet it still allows emergency alert services and legitimate organizations’ calls through. In 2014, the Nomorobo service blocked 15.1 million robocalls for the 190,000 VOIP customers who subscribe to his service. The blacklist is developed using numbers that have been reported to him or the FTC by consumers. Others are flagged by an algorithm that identifies suspicious calling patterns. Foss reports that Nomorobo stops about 87 percent of unwanted robocalls.

What about legitimate calls?

Customers who are concerned that legitimate robocalls will not be able to get through can submit those numbers so that they can be whitelisted and not blocked by his service. Foss claims that the error rate for blocking numbers unjustly is .18%.

An article on asks why the big phone companies have been unable to block robocalls in this way, and they say that because of the 1934 Telecommunications Act, phone companies have an obligation to complete phone calls regardless of who they are from.

Another challenge to maintaining a system based on blacklisting certain phone numbers and whitelisting others was brought up by CTIA is spoofing software, which allows callers to trick the caller ID system. Maintaining a database that could keep up with the rate at which spammers can generate spoofed numbers would be impossible to manage.

The FCC takes action

The Federal Communications Commission took public comments on the issue of whether or not phone carriers should be able to block robocalls outright. In June of 2015, the FCC published a news release about the steps they were taking to strengthen consumer protections against unwanted phone calls and text messages.

In the release, the FCC states that complaints related to unwanted phone calls are the largest category of complaints each month, citing 215,000 complaints about robocalls in 2014. This release outlined a package of declaratory rulings that affirm the consumer’s rights to control what kinds of telephone calls they want to receive. Among the new rulings that strengthen the Telephone Consumer Protection Act (TCPA) are the following changes:

  • Green light for “Do not disturb” technology
  • Empowering consumers to say, “Stop”
  • Reassigned phone numbers are not loopholes
  • Third-party consent
  • Affirming the law’s definition of auto-dialer

Aaron Foss’s Nomorobo service only works with VOIP phones.  Consumers who don’t have access to the service can manually block up to 20 phone numbers manually, depending on their phone carrier’s system. As of early 2015, the Nomorobo database had more than 850,000 numbers in its blacklist.