Legal Question in Civil Litigation in California

The offeror does not have to sign an offer for it to be valid and binding. What matters is whether or not it was authorized. An attorney has no power to bind his or her client to an offer or settlement without the client's authorization, which is why all wise attorneys get a written settlement agreement even after they exchange an offer and acceptance with the other attorney, but if a client has in fact authorized a settlement offer and it is accepted, it is binding regardless of whether the client signed anything. The trouble is that the communications between the client and attorney are privileged. So it is almost impossible to prove the client authorized a settlement if they repudiate it and say the attorney acted on their own. There is clear case law that an attorney cannot bind the client to a settlement offer or agreement the way a normal agent might. The principal of ostensible or apparent authority does not apply to attorneys. So in reality, it is nearly impossible to prove an offer is binding until it turns into a signed settlement agreement or is made in a settlement conference or other situation where there are witnesses other than the lawyer and client that the client authorized the settlement offer.

It's not enforceable pursuant to Code of Civil Procedure section 664.6. That section provides that a settlement agreement may be enforced, upon motion, as a judgment. But that section requires the settlement agreement outside the presence of the court to be signed by both parties.

With that said, it may be enforceable under general contract principles, as set forth by Mr. McCormick.