In a Ca civil case I settled with one of defendants.
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His attorney included a "defendant" that wasn't her client in the "release" section of the settlement doc.
My question is: doesn't this "defendant" need to sign the contract also, or does his name in the "release" paragraph binding.
The additional person does not need to sign the settlement document. Your release of claims against that person would be binding on you, whether or not that person is a signatory to that document.
He only needs to sign as to anything he gives up. By signing the release, you are bound as to all named defendants, regardless of their signature.