A business owner who signs a supplier’s credit application or commercial lease may believe the signature binds only the LLC. A creditor may believe it also binds the owner personally. In December 2025, the New Jersey Supreme Court addressed that problem directly in Extech Building Materials, Inc. v. E&N Construction, Inc. The decision is essential reading for both creditors and guarantors. A common setting for disputed personal guarantees is a commercial lease default involving continuing guaranty obligations.
The court focused on unambiguous personal intent
In Extech, the Court held that a valid personal guaranty of a company’s indebtedness requires the signer’s unambiguous manifestation of intent to be personally bound. The Court did not create a bright-line rule requiring two signatures. A single signature can sometimes bind both the company and its representative if the agreement explicitly makes that dual commitment clear.
The underlying credit form contained personal-guaranty language, but the Court concluded that the individual had not unambiguously assumed the obligation on the document before it. That result turned on the actual contract and signature context rather than a universal ban on guarantees.
New Jersey has a writing requirement
N.J.S.A. 25:1-15 provides that a promise to answer for another person’s obligation must be in writing and signed by the person assuming liability or an authorized agent. This is separate from proving that the underlying business actually owes the claimed amount.
For lenders, landlords and suppliers, the signature block, legal name of the obligor, definition of guaranteed debt, and any separate individual acknowledgment deserve careful drafting. Avoid relying on a sentence embedded above a corporate signature without evaluating whether it actually communicates personal assumption of liability.
Review scope, expiration and amendments
A business owner should ask whether the guaranty is unlimited or capped, continuing or transaction-specific, and whether it survives renewals, rent increases, transfers, assignments, or amendments to the primary agreement. Guarantees sometimes include waivers or acceleration provisions that are economically more significant than the base contract.
On a landlord-side lease, specify when the guaranty ends and what happens to arrears or claims already accrued. On the guarantor side, negotiate a release tied to a defined date, assignment, or satisfied payment condition rather than assuming the guaranty disappears when the tenant leaves.
Litigation begins with the complete contract packet
Before making a guaranty demand or responding to one, collect the signed agreement, credit application or lease, amendments, signature pages, account ledgers, relevant emails, and evidence of performance. Determine both the company’s liability and whether the guaranty ever formed.
Extech demonstrates why general assurances that a ‘guaranty is standard’ do not substitute for the actual words and signatures. Counsel should evaluate the governing law and any separate defenses before threatening personal collection.
Why the Supreme Court rejected a mechanical signature rule
In Extech Building Materials, Inc. v. E&N Construction, Inc., decided December 2, 2025, New Jersey’s Supreme Court confronted a supplier’s credit application containing guaranty language near a corporate signer’s signature. The Court rejected a rigid requirement that every guaranty have two signatures. But it also refused to impose personal liability where the document failed to manifest the signer’s individual assent unambiguously. This matters because the legal question is not merely how many signatures appear. It is whether the written agreement unmistakably shows that the individual voluntarily undertook a separate obligation to pay another party’s debt.
The Court identified workable ways to show that assent: a standalone guaranty, distinct corporate and individual signatures within the underlying agreement, or a single signature accompanied by explicit language making clear that it binds both capacities. The principle interacts with New Jersey’s Statute of Frauds, N.J.S.A. 25:1-15, which requires a signed writing for an undertaking to answer for another’s debt. A supplier cannot cure unclear language by saying that personal guaranties are routine in its industry; a business owner cannot assume that placing LLC after a signature defeats unmistakable guaranty terms.
Scope is the next dispute even when a guaranty exists
A well-drafted guaranty should answer more than whether the signer is personally bound. Does it cover only invoices under one purchase order or all future indebtedness? Does it survive renewal, amendment, assignment, ownership change or termination of the underlying contract? Are attorney fees, interest, collection costs and acceleration included? Is there a written cap or release process? A vendor seeking recovery should identify the precise contractual provision and prove the amount owed. A guarantor should examine whether the claimed debts fall within the undertaking and whether the creditor satisfied contractual notice or other conditions.
Consider a hypothetical business that originally opens a $25,000 supplier account and later expands into several projects after a change in ownership. The original credit form may have an individual’s signature, but that does not answer whether the signer’s promise extends to new purchases, a successor entity, or post-termination obligations. Collect each application, amendment, statement of account, credit increase, email approving new terms, and invoice-level payment history. A running balance alone may conceal credits, returns, disputed deliveries or debts belonging to a different contracting entity.
Contract design is cheaper than litigating signature intent
For new transactions, lenders, suppliers and landlords can reduce ambiguity by identifying the actual debtor, naming the guarantor in an individual capacity, defining the covered obligations, and using a separate unmistakable acknowledgment. For owners, the negotiation should address duration, exposure limits, release conditions and whether the guaranty ends after specified performance. In litigation, both sides should resist arguments based only on a template’s appearance; the governing text and legally relevant context control. The Extech decision is a reason to audit existing contract forms, not permission to treat every signed commercial agreement as a personal guaranty.
Sources and further reading
- New Jersey Supreme Court, Extech Building Materials, Inc. v. E&N Construction, Inc. (Dec. 2, 2025)
- New Jersey Statute of Frauds, N.J.S.A. 25:1-15
Need a review tied to your own records or deadline? Discuss a Personal Guaranty, or send a brief, nonconfidential inquiry. BOLO Health Law is based in New Jersey. This article is general information, not legal advice. Contact does not create an attorney-client relationship, and no outcome is guaranteed.