Can 3 people re write an existing agreement without all the original signatures?

Yes, three people can rewrite an existing agreement without all the original signatures, provided that they have the authority to modify the agreement and all parties involved in the original contract agree to the changes. It's important that the new document clearly states the intent to amend or replace the original agreement and includes signatures from the parties involved in the new version. However, the enforceability of the rewritten agreement may depend on the terms of the original contract and applicable laws.