Twelve of the country’s largest telephone companies on Thursday pledged to implement new technology to spot and block robocalls, part of an agreement brokered between the industry and 51 attorneys general to combat the growing telecom scourge. From a report: The new effort to be announced in Washington commits a wide array of companies in the absence of regulation to improving their defenses and aiding law enforcement in its investigations into illegal spam calls, which rang Americans’ phones an estimated 4.7 billion times in July alone. Under the agreement, the 12 carriers have agreed to implement call-blocking technology, make anti-robocall tools available for free to consumers and deploy a new system that would label calls as real or spam. Known by its acronym, STIR/SHAKEN, the technology takes aim at a practice known as spoofing, where fraudsters mask their identities by using phone numbers that resemble those that they’re trying to contact in a bid to get victims to pick up and surrender their personal information. Signing the pledge are larger mobile carriers, such as AT&T, Comcast, Sprint, T-Mobile and Verizon, which already have said they would implement such robocall protections and in some cases have started testing them around the country. Other carriers adopting the pledge include Bandwidth, CenturyLink, Charter, Consolidated, Frontier, U.S. Cellular and Windstream.