This is not true and a myth! Illegal callers do not need to get the DNC which has to be paid for along with information proof of business. The illegal callers use dialers and other methods such as computer and all they have to do is plumb in numbers from a to z.. The DNC can't protect you from illegal callers and is only aimed for telemarketers.
Caller ID showed Day, J. Solicitation call for Electric Coalition or something like that. Selling Solar products. Knew my first name. When he said my electric bill had to be at a minimum of $125 a month to qualify, I laughed. My bill is barely $50.00. I thanked him for his 5 minute speech and ask to be removed from their call list.
ID says J Day. He knows my name. Wants to know if I think I qualify for something or another. I tell him to take me off his list and he yells, "Do you think you qualify?" I hung up and blocked him.