The rule in the First Department is that when an attorney hits "Send" with the intention of relaying a settlement offer or acceptance, and the email account is identified in some way as the attorney's own, it is not necessary for the attorney to type his own signature. However, this does not mean that every email purporting to settle a dispute will be unassailable evidence of a binding settlement. First, because there is a rebuttable presumption that an email from an attorney's account is authentic, a party that claims an email was the product of a hacker may challenge its authenticity. Second, as with all enforceable settlements, an email settlement must set forth every material term.
Matter of Philadelphia Ins. Indem. Co. v. Kendall, NY Slip Op 04284 (1st Dep't July 8, 2021)