When you sign a document on another person’s behalf, the formal legal term is per procurationem, almost always written as the abbreviation “p.p.” The everyday phrase for the same thing is signing “as agent” or “in a representative capacity,” and the legal authority usually comes from a power of attorney, a guardianship order, or a corporate resolution naming you as an authorized signatory. Whatever the arrangement, two things have to be true: you need actual authority to sign, and the signature itself has to show you’re signing for someone else and not as yourself. Without both, the signature can be treated as forgery.
Per Procurationem (P.P.)
Per procurationem is Latin for “through the agency of.” You’ll rarely see the full phrase outside legal filings; in business letters and correspondence it appears as “p.p.” placed before the signer’s name. The abbreviation tells anyone reading the document that the person who physically signed was acting as an authorized representative rather than as a party in their own right.
The usual convention puts “p.p.” before the name of the person doing the signing, followed by the name of the person being represented. If Jane Smith signs a letter on behalf of John Doe, the signature block reads something like: “p.p. Jane Smith, for John Doe.” Placement varies a bit by industry and country, but the point is always to make the representative relationship unmistakable on the face of the document.
Signing Under a Power of Attorney
A power of attorney is the written document that most often gives one person legal authority to sign for another. The person granting the authority is called the “principal,” and the person receiving it is the “agent” or “attorney-in-fact.” The principal decides how broad or narrow the authority is: it can cover a single real estate closing or every financial decision the principal might ever need to make. The document itself typically has to be signed by the principal, witnessed, and notarized to be legally effective.
When you sign something under a power of attorney, the format matters as much as the authority itself. Write the principal’s name first, then your own name with a designation showing you’re acting as agent. A standard version looks like this:
“John Doe by Jane Smith, as Agent” or “John Doe by Jane Smith, under POA.”
That format puts the other party on notice that Jane Smith isn’t making a personal commitment. She’s signing for John Doe, and John Doe is the one bound by the document. Skip the representative designation and you can end up personally liable on something you never meant to be a party to.
Whoever signs under a power of attorney owes a fiduciary duty to the principal: act in the principal’s interest, keep careful records, and avoid self-dealing. A court can order an agent who misuses the authority to repay losses, cover legal fees, and in some cases pay additional damages. Authority also ends automatically when the principal dies, and continuing to sign after that point can bring both civil liability and criminal charges.1Uniform Law Commission. Uniform Power of Attorney Act
Other Ways You Can Be Authorized to Sign
A power of attorney isn’t the only route. Depending on the situation, the authority to sign for another person can come from several different legal arrangements.
Guardianship and Conservatorship
If someone can’t manage their own affairs and never set up a power of attorney, a court can appoint a guardian or conservator to sign for them. This takes a court proceeding, and a judge decides the scope of what the appointee can do. Some states use “guardian” for personal decisions and “conservator” for financial matters; others use the terms differently. In every case the appointee owes a fiduciary duty to the person being protected and typically has to file regular reports with the court.
Healthcare Agent or Proxy
A healthcare power of attorney (also called a healthcare proxy or medical power of attorney) authorizes someone to sign off on medical decisions if you can’t communicate your own. It’s a separate document from a financial power of attorney. A financial POA gives no authority over medical care, and a healthcare POA gives no access to bank accounts or property. You can name the same person for both roles, but you need two documents to do it.
Authorized Signatory
In a company or other organization, an “authorized signatory” is a person named in the entity’s bylaws or by board resolution as having power to sign contracts for the organization. The scope depends on the governing documents. A signatory with authority over routine vendor contracts may not have authority to sign a merger agreement, and the signature should identify the entity being bound along with the signer’s title.
Proxy
A proxy is narrower and tied to a specific event, usually a vote. Shareholders who can’t attend a meeting in person commonly submit a proxy letting someone else cast their vote. The authority expires when the meeting ends.
Documents You Can’t Sign for Someone Else
Even a broad power of attorney has limits. Certain documents require the person’s own signature and can’t be delegated to anyone:
- Wills. An agent cannot sign or change a will on the principal’s behalf. A will requires the testator’s personal intent and signature.
- Ballots. Voting is a personal right, and no power of attorney grants the authority to vote for someone else in a public election.
- Sworn affidavits based on the signer’s own firsthand knowledge, and certain court filings requiring a party’s personal oath.
- Marriage licenses. Most states don’t permit proxy marriages, and the few that do generally limit them to active-duty military members stationed abroad.
Before signing anything as a representative, check that the document type actually allows representative signatures in the first place.
What Happens If You Sign Without Authority
Signing someone else’s name without their knowledge or legal authorization is forgery. The entire difference between a lawful representative signature and a forged one is whether proper authority existed at the moment of signing. Without it, the signature is invalid, the document is generally unenforceable, and the person who signed can face criminal charges.
At the federal level, forging U.S. government obligations or securities carries a maximum sentence of 20 years in prison.2Office of the Law Revision Counsel. 18 USC 471 – Obligations or Securities of United States Fraud involving identification documents brings penalties from 5 to 15 years depending on the document, and up to 30 years if connected to terrorism.3Office of the Law Revision Counsel. 18 USC 1028 – Fraud and Related Activity in Connection With Identification Documents State forgery laws vary; some treat forgery of low-value documents as a misdemeanor and reserve felony charges for higher-value instruments like deeds or financial contracts.
Civil liability follows the same logic. Under the Uniform Commercial Code, if you sign a check or other negotiable instrument as a representative and the signature clearly shows both the name of the person represented and your representative capacity, only the represented person is bound. Leave off the representative designation and you can be held personally liable on the instrument.4Legal Information Institute. UCC 3-402 – Signature by Representative A signature made with no authority at all is treated as ineffective against the person whose name was used; the unauthorized signer becomes personally liable instead.5Legal Information Institute. UCC 3-403 – Unauthorized Signature Anyone who presents a forged instrument for payment can also be forced to repay the full amount plus expenses under the UCC’s presentment warranties.6Legal Information Institute. UCC 3-417 – Presentment Warranties
If you have the authority and sign correctly, you’re signing per procurationem. If you don’t, you’re committing forgery. The format of the signature is what tells the world which one it is.