You don’t want your customers to know who you are?
It seems to me that they have the option to require this of you. They are not forbidden.
You can either comply or find yourself new clients.
“You dont want your customers to know who you are?”
Customers knowing me and my work IS TOTALLY different than their staff and accountants and payer services having my SSN.
I do not advertise my SSN now do I.
“It seems to me that they have the option to require this of you. They are not forbidden.”
42 USC 408 makes it a FELONY to use threat, duress, or coercion to try to force a person by fear or deceit to provide his SSN in an unlawful manner.