I'm dealing with the similar situation. I left my previous employment due to illegal activities the owner was getting into. As of yesterday, I started receiving phone calls pertaining to him. How can my personal cell phone # be divulged without my permission?? Is that legal?? There is so much more behind this, but I am starting my case of deflamation of character and need to get all my ducks in a row first..

Just change your phone number and you won't have to deal with this person any longer. Why does everyone want to automatically sue everyone else when a simple change of phone number is in order?

Once your number is changed no one will have it unless you give it to them.

I'm dealing with the similar situation. I left my previous employment due to illegal activites the owner was getting into. As of yesterday, I started receiving phone calls pertaining to him. How can my personal cell phone # be divulged without my permission??? Is that legal??? There is so much more behind this, but I am starting my case of deflamation of charactor and need to get all my ducks in a row first..

Who did you find to represent you? No attorney worth his or her salt would even entertain this because you don't have a case. Nothing has been done to damage your character; I don't see what you think you could possibly sue for.

If they're calling you, simply say that it is not his phone number, it has never been his phone number and if they continue to call, you will contact the FCC.

Who did you find to represent you? No attorney worth his or her salt would even entertain this because you don't have a case. Nothing has been done to damage your character; I don't see what you think you could possibly sue for.
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Correct. The divulging of one's phone number to other persons is not defamation. Not even close. However OP wrote that there "is so much more behind this". Perhaps we were not told the basis if the defamation claim.

It may be unethical, but I doubt if it is illegal.

It is not illegal, if you sgined a contract with them not to give it out, then you could sue for breach of contract, but you are free to give out anyone's number as are they free to give out your number.