CNET: “A big deadline in the fight to beat back those annoying robocalls is coming tomorrow. As of June 30, every major voice provider in the US, including phone companies AT&T, Verizon and T-Mobile and cable provider Comcast, will have to implement a technology called Stir/Shaken.That’s good news for everyone whose phone has been jangling with bogus phone calls involving health-related scams, expiring car warranties and fake banks offering nonexistent interest-rate discounts for credit cards. For years, the scourge of illegal robocalls has plagued the public. It’s the No. 1 consumer complaint and a top priority at the Federal Communications Commission. US consumers have received just under 22 billion robocalls in the first five months of the year, on pace to hit over 52 billion robocalls for the year, according to YouMail, a company specializing in blocking robocalls…”

See also via the FCC – “What Does STIR/SHAKEN Mean? STIR/SHAKEN is a framework of interconnected standards. STIR/SHAKEN are acronyms for the Secure Telephone Identity Revisited (STIR) and Signature-based Handling of Asserted Information Using toKENs (SHAKEN) standards. This means that calls traveling through interconnected phone networks would have their caller ID “signed” as legitimate by originating carriers and validated by other carriers before reaching consumers. STIR/SHAKEN digitally validates the handoff of phone calls passing through the complex web of networks, allowing the phone company of the consumer receiving the call to verify that a call is in fact from the number displayed on Caller ID…”