An AI agent that sends email from your account, ending with your name and title, produces something courts have repeatedly treated as a signed email. Whether that email binds you depends on facts no software decides: whether you authorized the agent, whether the email shows an intention to authenticate it, and whether the transaction needs a formality an email cannot meet. The cases below, from England, New York, Canada and the Ninth Circuit, show how judges have approached each of those questions.
This is general information about published decisions and statutes, not legal advice. The cases involve people and simple email software; no court we know of had ruled on an email written and sent by an AI agent as of October 7, 2026, so applying them to agents is our reading.
The short answer
- A signature block can sign an email. An English court held in 2019 that a solicitor's automatic Outlook signature signed a contract for land, and New York's appellate courts treat a typed name at the end of an email as a signed writing.
- Software acting for you can make contracts for you. US federal law and the Uniform Electronic Transactions Act say a contract cannot be denied effect solely because an "electronic agent" formed it, as long as the agent's action is attributable to the person to be bound.
- Companies answer for their bots. A Canadian tribunal held Air Canada liable for its chatbot's wrong answer, and the Ninth Circuit called a shopping agent "a tool, not a person" for the purposes of a computer-access statute.
- So treat your agent's signature block as yours. When an agent appends your full signature, it adds the part of the email that courts read as you standing behind the content.
Can an automatic email signature count as a signature?
Neocleous v Rees (England, 2019)
A dispute over a boat landing plot was settled by email between the parties' solicitors. The defendant's solicitor confirmed the terms in an email that ended "Many thanks", followed by a block Outlook added to every email he sent: "David Tear, Solicitor and Director, For and on behalf of AWB Charlesworth Solicitors". The defendant later argued that the deal failed the rule that a contract for land must be "signed by or on behalf of each party" (section 2(3), Law of Property (Miscellaneous Provisions) Act 1989), because nobody had signed anything: the name was generated automatically.
Judge Pearce, sitting in the County Court at Manchester, disagreed. The judgment records that "It is common ground that such a footer can only be present because of a conscious decision to insert the contents, albeit that that decision may have been made the subject of a general rule that automatically applied the contents in all cases." It also notes that the sender knew his name was being added, that "Many Thanks" connected the name to the content, and that the block sat where a signature conventionally sits. A footnote observes that the "Microsoft Outlook programme calls this a 'signature'". According to Legal Futures' report, the court ordered specific performance of the settlement.
What carries over to agents: the court looked at the setting-up of the automatic signature as the decision that counted. An agent configured to append your signature to every email it sends looks much like that rule, as far as the recipient can tell.
J Pereira Fernandes v Mehta (England, 2006)
The other side of the line. An email offering a personal guarantee carried no name in its text, only the sender's address, which the email system put in the header. The court held that was not a signature for the Statute of Frauds. The same judgment said that if a party or a party's agent sending an email "types his or her or his or her principals' name to the extent required or permitted by existing case law in the body of an email, then in my view that would be sufficient signature". An agent that sends with no signature block at all may leave an email unsigned in this sense; one that types your name may not.
Golden Ocean v Salgaocar (Court of Appeal, 2012)
A guarantee for a charter was agreed through a chain of shipbrokers' emails. The last one ended with the broker's first name, "Guy". Tomlinson LJ wrote: "In my judgment Mr Hindley put his name, Guy, on the email so as to indicate that it came with his authority and that he took responsibility for the contents. It is an assent to its terms. I have no doubt that that is a sufficient authentication." Whether the broker had his principal's authority to sign the guarantee was left for trial. Both parts, the name and the authority, are the questions an agent's email raises.
WS Tankship v Kwangju Bank (England, 2011) and the Law Commission
In WS Tankship (2011), a bank's name in the header of a SWIFT message, generated by the system, was treated as a sufficient signature, because the bank chose to send through that system. The point may not have been needed for the result, so treat it as persuasive. The Law Commission's 2019 report on electronic execution lists "a name typed at the bottom of an email" and "the header of a SWIFT message" among electronic forms courts have accepted, and states the rule: "An electronic signature is capable in law of being used to execute a document (including a deed) provided that (i) the person signing the document intends to authenticate the document and (ii) any formalities relating to execution of that document are satisfied."
US law already lets software agents make contracts for you
E-SIGN: contracts formed by electronic agents
The federal E-SIGN Act defines an "electronic agent" as "a computer program or an electronic or other automated means used independently to initiate an action or respond to electronic records or performances in whole or in part without review or action by an individual at the time of the action or response" (15 U.S.C. 7006(3)). That description fits an AI agent sending email with drafts turned off.
Section 7001(h) then says a contract "may not be denied legal effect, validity, or enforceability solely because its formation, creation, or delivery involved the action of one or more electronic agents so long as the action of any such electronic agent is legally attributable to the person to be bound." An electronic signature, in turn, is one "executed or adopted by a person with the intent to sign the record" (7006(5)).
UETA: attribution and automated transactions
Most states have enacted the Uniform Electronic Transactions Act. In Texas's version, for example (Business and Commerce Code chapter 322):
- Attribution (section 9 of the uniform act). "An electronic record or electronic signature is attributable to a person if it was the act of the person." That can be shown "in any manner".
- Automated transactions (section 14). "A contract may be formed by the interaction of electronic agents of the parties, even if no individual was aware of or reviewed the electronic agents' actions or the resulting terms and agreements."
The hinge in both statutes is attribution: whether the agent's act counts as yours. Deploying an agent on your mailbox and telling it what to do is the kind of fact a court may weigh on that question.
New York: a typed name signs, an automatic block was argued
In Stevens v Publicis (Appellate Division, First Department, 2008), "Each of the e-mail transmissions bore the typed name of the sender at the foot of the message", and the court held: "The e-mails from plaintiff constitute 'signed writings' within the meaning of the statute of frauds, since plaintiff's name at the end of his e-mail signified his intent to authenticate the contents".
In Naldi v Grunberg (same court, 2010), the defendant argued that a broker's email "contained only the automatically generated identification block of the brokerage firm from which it was sent and therefore was not properly subscribed." The court confirmed that "an e-mail will satisfy the statute of frauds so long as its contents and subscription meet all requirements of the governing statute", but dismissed the claim for a different reason and did not decide the signature-block point. In New York, whether an automatic block subscribes an email is still open.
Companies answer for what their bots say
Moffatt v Air Canada (British Columbia, 2024)
Air Canada's website chatbot told a customer they could claim a bereavement fare after travel; the airline's policy said otherwise. Before the Civil Resolution Tribunal, Air Canada argued it could not be liable for information from its agents, "including a chatbot." The tribunal's answer, at paragraph 27 of 2024 BCCRT 149: "In effect, Air Canada suggests the chatbot is a separate legal entity that is responsible for its own actions. This is a remarkable submission. While a chatbot has an interactive component, it is still just a part of Air Canada's website. It should be obvious to Air Canada that it is responsible for all the information on its website."
The tribunal found negligent misrepresentation. It is a small-claims decision without binding precedent, about a website chatbot; a company should still expect the same reasoning when its agent writes to a customer in the company's name.
Amazon v Perplexity (Ninth Circuit, 2026)
Amazon sued Perplexity over Comet, a browser whose AI "Assistant" shops on Amazon for the user. On August 4, 2026, the Ninth Circuit vacated a preliminary injunction under the Computer Fraud and Abuse Act. The opinion reasons: "However advanced the Assistant currently is, it is a tool, not a person for statutory purposes." And: "It is the user who 'accesses' Amazon's computers, with the help of the Assistant to carry out specific acts on Amazon.com."
The court drew its own limits: "We do not establish a new legal regime governing agentic AI. We do not address whether in other contexts, including tort claims, Perplexity can avoid liability for the Assistant's actions." Read with Moffatt and the electronic-agent statutes, it points one way: the law tends to treat an AI agent's acts as the acts of the person using it.
What your agent's signature block may mean
Put together, the cases suggest the signature block on an agent-sent email can do three things:
- Make the email look signed by you, including emails you never read. A full name, title and company at the foot of an email are what Neocleous and Stevens treated as authentication.
- Answer the attribution question. Under E-SIGN and UETA the issue is whether the agent's act is yours. An email sent from your account, under a signature you configured, gives a recipient good reason to think it is.
- Show who stands behind the email. That cuts both ways: it is what makes an agent's email trustworthy to the recipient, and what makes it harder to disown later.
The risk concentrates in emails that accept an offer, agree a price, confirm a settlement or promise a delivery date, and in transactions with formal requirements of their own (deeds, wills and some land transfers still need more than an email in many places).
Controls that keep an agent's email under your control
- Keep drafts on for anything that commits you. Most assistants ask before each send by default. Leave that on for contracts, prices, settlements and anything a recipient could rely on, and limit fully automatic sending to replies that commit to nothing.
- Say in the signature who sent it. An agent's signature that names the agent and the person or company it acts for ("Sent by Ava, an AI assistant, on behalf of Dana Lee, Example Ltd") tells the recipient what they are reading. The European Commission's 2026 guidelines on the EU AI Act say agents should disclose both their artificial nature and "the person on whose behalf they are acting". AI email disclosure has wording you can adapt, and Should AI sign emails as you? weighs the options.
- Give each agent its own signature. One signature per agent keeps the record clear about which agent sent what. Signatoro serves each agent its signature at send time over MCP or the REST API, so the agent appends the signature you configured, in its current version, on every email.
- Keep the company's required lines on agent mail. A UK company's email still needs its trading disclosures, and US commercial email still needs what CAN-SPAM asks for. On Signatoro's larger company plans, the owner's footnote line goes under every member's signature, agents included (see pricing).
- Keep the record. Sending through your own mailbox puts every agent email in your Sent folder, which is where a dispute will start.
AI agent email legal questions
Is an email legally binding if an AI sent it?
It can be. US law says a contract cannot be denied effect solely because an electronic agent formed it, as long as the agent's action is attributable to the person to be bound, and courts in England and New York have treated names at the foot of emails as signatures. Whether a particular email binds you depends on your authority given to the agent, its content and the law that governs the deal. This is general information, not legal advice.
Does an automatic email signature count as a signature?
Sometimes. In Neocleous v Rees (2019) an English court held that a solicitor's automatic Outlook signature block signed a contract for land, because setting it up was a conscious decision to sign off every email with it. In New York the question was argued in Naldi v Grunberg (2010) and left undecided.
Am I responsible for what my AI agent says in an email?
Generally, expect to be. A Canadian tribunal held Air Canada responsible for its chatbot's statement, calling the argument that the bot was a separate entity "a remarkable submission". Utah's AI law adds that, under the consumer protection statutes its Division of Consumer Protection enforces, it is not a defense that generative AI "made the violative statement".
Should my AI agent sign emails with my name?
Only where you have authorized it to act for you, and with a signature that says an AI assistant sent the email on your behalf. A full personal signature on an unreviewed email makes it look like you wrote and approved it.
Can an AI agent sign a contract for me?
US electronic-transactions law allows contracts formed by electronic agents when their actions are attributable to the person bound, so an agent's email can form a contract in some cases. Documents with formal requirements, such as deeds, often need more. Keep drafts on and approve any email that agrees terms.
Sources
Checked on October 7, 2026:
- England and Wales: Neocleous v Rees [2019] EWHC 2462 (Ch); report of the order in Legal Futures, September 30, 2019
- England and Wales: J Pereira Fernandes SA v Mehta [2006] EWHC 813 (Ch)
- England and Wales: Golden Ocean Group Ltd v Salgaocar Mining Industries [2012] EWCA Civ 265
- England and Wales: WS Tankship II BV v Kwangju Bank [2011] EWHC 3103 (Comm)
- Law Commission: Electronic execution of documents (Law Com No 386), September 4, 2019
- United States Code: 15 U.S.C. 7001 and 15 U.S.C. 7006 (E-SIGN Act)
- Texas: Business and Commerce Code chapter 322 (Uniform Electronic Transactions Act)
- New York Appellate Division: Stevens v Publicis S.A., 50 AD3d 253 (2008)
- New York Appellate Division: Naldi v Grunberg, 80 AD3d 1 (2010)
- British Columbia Civil Resolution Tribunal: Moffatt v. Air Canada, 2024 BCCRT 149
- US Court of Appeals, Ninth Circuit: Amazon.com Services, LLC v. Perplexity AI, Inc., No. 26-1444, August 4, 2026
- Utah Legislature: SB 226, Artificial Intelligence Consumer Protection Amendments (2025)
- European Commission: Guidelines on the transparency obligations under Article 50 of the AI Act, July 20, 2026