It’s a legal gray area that some companies are already taking advantage of, but the FCC is currently deciding if it wants to make it officially acceptable. Telemarketers and robocall services hope to take advantage of a loophole that would allow them to skip the call and just flood your voicemail inbox with messages.
Source: Gizmodo – FCC Considering Nightmare Rules That Allow Telemarketers to Go Straight to Voicemail