Why did the seller not sign the counter offer?
You may receive a Seller's Counter Offer with no signatures. These forms are generated by the corporate/bank's Asset Manager or the outsource company (and often come to the Listing agent as an email attachment). Once an offer is accepted the entire "package" (which may include the Offer as well as Counters, Addendums, copy of the check, et.al.) is sent to the bank for signatures.
Once you are informed that your offer is accepted, it is. (acceptance may be accompanied by the aforementioned worksheet). REO departments and Asset managers give the "OK" and then go to their managers for signatures. We realize it is an unusual business practice to agree to offers orally, but corporate sellers often have their own way of doing business and we appreciate your understanding.