An authorized signature is a signature made by someone who has been given legal power to act for another person, company, or organization, so that the signature binds the represented party rather than only the individual who wrote it. Get the authority or the formatting wrong and two bad things can happen: the agreement may not bind who you thought it did, or you may have signed yourself personally onto the hook.
Who Can Sign for Someone Else
Authority to sign has to come from somewhere identifiable. A person cannot simply claim to represent a company or another individual and make that binding.
Inside a company, authority flows from the governing documents. Corporate bylaws spell out which officers and directors can execute contracts, and the board of directors can pass resolutions granting specific employees the power to sign particular types of agreements. A CEO usually has authority to sign contracts in the ordinary course of business, but that authority does not automatically extend to extraordinary transactions like selling the company’s primary asset. Partnership agreements do similar work for partnerships, defining which partners can bind the business. Without clear language, any general partner might commit the others to debts or contracts they never agreed to. Trust documents outline what a trustee can and cannot do with trust property.
For individuals, the usual mechanism is a power of attorney. The person named in the document, called the agent, can take any action the document permits on behalf of the person who created it. Powers of attorney range from broad grants covering nearly all financial and legal decisions to narrow authorizations limited to a single transaction. Read the document before you rely on it: a POA for real estate does not authorize the agent to sign a business contract.
Apparent Authority and Ratification
Actual authority is not the only route. Two doctrines expand the picture.
Apparent authority arises when a principal’s own conduct leads a third party to reasonably believe an agent has power to act, even when no such power was formally granted. If a company gives someone an executive title, office space, and business cards, and that person signs a vendor contract, the vendor may have a valid claim against the company even if the “executive” was never authorized to sign anything. The principal’s behavior created the appearance of authority, and the law protects a third party who relied on that appearance in good faith.
Ratification runs the other way. When someone signs without proper authority, the principal can later approve the act and make it binding retroactively. Under the Uniform Commercial Code, an unauthorized signature on a negotiable instrument can be ratified for all purposes.1Legal Information Institute. Uniform Commercial Code 3-403 – Unauthorized Signature Once ratified, the signature is treated as if it had been authorized from the start.
How to Format the Signature Block
Formatting is not a formality. Under the UCC, a representative who signs a negotiable instrument avoids personal liability only if the signature unambiguously shows it was made in a representative capacity and the represented party is identified in the document.2Legal Information Institute. Uniform Commercial Code 3-402 – Signature by Representative Miss either element and you may have signed yourself into personal liability.
A signature block for someone signing on behalf of a company or another person should include three things: the name of the entity or person being represented, the signer’s own name, and the signer’s title or capacity. In practice, it looks like this:
ABC Corporation
By: [signature]
Jane Smith, Chief Financial Officer
The word “By:” is doing real work. It signals that the person is signing in a representative capacity, not as an individual. Leaving it out, or signing without any indication of your role, is where problems start. This matters most on checks, promissory notes, and other negotiable instruments, where the UCC rules on personal liability apply strictly.
When an Authorized Signer Ends Up Personally Liable
The bigger practical risk with authorized signatures is not fraud. It is an authorized representative who signs carelessly and ends up personally liable for an obligation that should belong to the company.
Under UCC ยง 3-402, if the form of the signature does not clearly show representative capacity, or if the represented party is not identified in the instrument, the representative is personally liable to a holder in due course who took the instrument without knowing the representative was not supposed to be personally liable.2Legal Information Institute. Uniform Commercial Code 3-402 – Signature by Representative Against other parties, the representative can try to prove the original parties did not intend personal liability, but that is a burden of proof you do not want to carry.
One practical exception: if a representative signs a check drawn on an account that identifies the represented party (the company name is printed on the check), the signer is not personally liable on the check even without noting representative status.2Legal Information Institute. Uniform Commercial Code 3-402 – Signature by Representative The check does the identifying itself. This exception applies only to checks, not to promissory notes, contracts, or other instruments.
Beyond negotiable instruments, an agent who signs any document while claiming authority they do not actually have is treated as having warranted that they possessed that authority. If the principal turns out not to be bound, the third party who relied on the agent can sue the agent personally for the loss caused by the false claim. This liability applies even when the agent honestly believed they had authority.
When Someone Signs Without Authority
An unauthorized signature is generally ineffective as the signature of the person it claims to represent. Under the UCC, an unauthorized signature operates only as the signature of the person who actually made it.1Legal Information Institute. Uniform Commercial Code 3-403 – Unauthorized Signature If someone forges a company officer’s name on a check, the company is not liable on the check. The forger is.
When an organization requires multiple signatures to authorize a transaction and one of those signatures is missing, the entire signature is treated as unauthorized.1Legal Information Institute. Uniform Commercial Code 3-403 – Unauthorized Signature Businesses that use dual-signature requirements on large checks or contracts as an internal control need to enforce them; if only one required signer signs, the document does not bind the organization.
The unauthorized signer does not escape either. The UCC states that its provisions making an unauthorized signature effective for certain purposes do not affect the civil or criminal liability of the person who made it.1Legal Information Institute. Uniform Commercial Code 3-403 – Unauthorized Signature Forging a signature can lead to fraud charges, and even an innocent overstep can result in personal financial liability to a third party who relied on the signature.
Do Electronic Signatures Count
Yes. An authorized signature does not have to be handwritten. Under the Electronic Signatures in Global and National Commerce Act, a signature or contract cannot be denied legal effect solely because it is in electronic form, and this applies to any transaction affecting interstate or foreign commerce.3Office of the Law Revision Counsel. 15 USC 7001 – General Rule of Validity At the state level, 49 states plus the District of Columbia have adopted the Uniform Electronic Transactions Act, which gives electronic signatures and records the same legal standing as their paper equivalents.
An electronic signature can be any electronic sound, symbol, or process attached to a record and executed with the intent to sign. Clicking an “I agree” button, typing your name in a signature field, or using a digital signature platform all qualify. The same authority rules apply. An employee who e-signs a contract on behalf of a company still needs proper authority. The medium changes; the legal requirements do not. When consumer disclosures are involved, the signer must affirmatively consent to receiving records electronically before e-signatures satisfy legal writing requirements.3Office of the Law Revision Counsel. 15 USC 7001 – General Rule of Validity
How to Verify the Other Side’s Authority
Trusting that someone has authority is a risk. Verifying takes a few steps and can prevent disputes that are far more expensive than the time spent checking.
The most direct approach is documentation. Ask for a copy of the board resolution granting signing authority, the relevant sections of the company’s bylaws, or the power of attorney. A well-drafted board resolution specifies which individuals can sign, what types of documents they can execute, and any dollar limits on their authority.
For corporate entities, public records offer an independent check. Most states maintain business entity filings that identify a company’s officers, directors, and registered agent. These records will not tell you everything about internal signing authority, but they confirm the entity exists and identify who is publicly associated with it.
When the stakes are high, contact the represented party directly. A call to the company’s legal department or the principal’s own attorney can confirm whether the person across the table has the power they claim. Experienced deal lawyers do this routinely, and no one with legitimate authority will object.
A Note on IRS Filings
Tax matters follow their own rules. A general power of attorney is not enough to let someone represent you before the IRS. You have to file Form 2848, Power of Attorney and Declaration of Representative, and the person you name must be eligible to practice before the IRS, generally an attorney, CPA, enrolled agent, or another recognized tax professional. A properly filed Form 2848 lets your representative receive your confidential tax information and act on your behalf in IRS matters.4Internal Revenue Service. About Form 2848 – Power of Attorney and Declaration of Representative If you skip it, your agent may be turned away at the door regardless of what other authority you have granted them.