Seals on Contracts: When a Signature Alone Won't Close the Deal

You sign a contract and send it back. A week later the other side's lawyer returns it, almost apologetically: could you also affix your company seal? You wonder what they think the signature was for. They wonder why you sent an unsealed document as if it were final.

Neither party is wrong. They are just operating in different signing cultures, and contracts are the exact place where those cultures collide. In much of East Asia, a contract without a seal is a draft. In most of the Anglophone world, a contract without a signature is a draft. And in a growing number of cross-border deals, both sides end up needing both — plus a quiet ten-minute negotiation about what "executed" means.

This article is about the practical side: when you need a seal on a contract, where it goes, what the page-sealing ritual actually accomplishes, and how to handle the increasingly common situation where one party thinks in seals and the other thinks in ink.

Why a signature is sometimes not enough

The idea that a written name means a person agreed to something is a convention, not a law of nature. It took centuries to settle in the West, and even there it did not fully displace seals — English common law required seals on deeds until surprisingly recently, and "signed, sealed, and delivered" is not a figure of speech.

In jurisdictions where company seals carry legal weight, the logic is different. A person signs with their hand, but a company is not a person. The seal is the company's mark. It says: this is not one employee's opinion — this is the entity acting. That is why China's contract seal (合同专用章) is a distinct object from the company's general seal, registered separately and kept under different custody. It is why Japanese companies use a jitsu-in (registered seal) for major agreements rather than a mitome-in (casual stamp). The seal maps to the concept of institutional authorization in a way that a personal signature cannot — even if the person signing is the CEO.

Does this mean you must seal a contract in those jurisdictions? Not always, and the honest answer is frustratingly jurisdiction-specific. Electronic seals in China, hanko in Japan, and dojang in Korea each explain the local rules. The safe summary: in most of East Asia, a contract sealed and signed is stronger than one that is only signed. Even where the law does not technically require a seal, the court, the bank, or the counterparty's compliance officer may practically expect one.

Where to place the seal on a contract

The default position is near the signature, and the seal placement guide covers the general principles. But contracts have their own conventions.

Next to or overlapping the signature. The most common placement in Chinese and Japanese contract practice. The seal impression sits beside the signatory's name or partially overlaps it, visually linking the person who signed to the entity they represent. In Chinese commercial practice, the overlap between seal and signature is intentional — it makes it harder to forge one without the other.

On the signature block. In jurisdictions where the seal substitutes for a signature (some Japanese agreements use only a seal impression, no handwriting), the seal goes in the signature block itself. The impression is the execution mark.

On the final page near the date. Some conventions place the seal at the bottom of the last page of terms, near the execution date. This signals that the version of the document bearing this seal is the one the party agreed to, as of this date. If the contract is amended later, the amended version gets a new impression.

On each party's copy. When each side keeps an original, each original gets sealed. In Chinese practice, this is distinct from page-sealing (covered below) — it is about making sure every copy that could be presented as "the contract" bears the mark.

The practical point: ask your counterparty where they expect the seal before you place it. There is no universal rule, and placing a seal in the wrong spot is not a legal problem but it does generate a round of questions you could have avoided.

Page-sealing: the ritual of stamping every page

If you have not encountered this before, it looks strange. The parties seal not just the signature page but every page of the contract — sometimes across the spine, sometimes in the margin, sometimes partly overlapping the text. The Chinese term is 骑缝章 (qí féng zhāng), literally "riding-the-seam seal." The Japanese equivalent is 契印 (keiin).

The purpose is simple and practical: it prevents page substitution. If every page bears a seal impression that aligns across the edge of the stack, you cannot swap page four for a different page four without breaking the visual chain. It is a physical tamper-detection mechanism, invented long before PDF digital signatures existed.

How it works in practice:

Fan or offset the pages so each page's edge is slightly exposed.
Press the seal across the exposed edges so that each page catches a slice of the impression.
When the pages are squared up, each individual page shows a partial seal mark. Laid out in order, the marks reconstruct the full impression.

In some practices, the approach is simpler: a full seal impression in the margin of every page, or a smaller stamp. The tamper-detection value varies — a per-page stamp is easier to forge than a riding-the-seam chain — but the organizational value is the same: every page is visibly claimed by the sealing party.

Is page-sealing required? Rarely by law. Almost always by institutional habit. If your Chinese counterparty's legal department page-seals, they will expect you to do the same. The good news is that with a digital seal and a PDF tool, this takes minutes rather than the physical gymnastics of the paper version.

When one side seals and the other signs

This is the situation that generates the most confusion, and it happens in almost every cross-border contract between an East Asian company and a Western one.

The East Asian party seals and signs. The Western party signs only. The document now has an asymmetry that makes nobody's legal team perfectly comfortable.

The practical question is not "is this valid?" — it is "will this be challenged?" And the answer depends on the forum. A Chinese court is more comfortable with a seal than with a foreign signature it cannot easily verify. A New York court has never heard of a company chop and does not care what shape it is. If a dispute lands in arbitration, the arbitrator will ask whether each party executed the document according to its own formalities — which is the actual legal standard in most international contracts.

So the safest approach for cross-border contracts:

Each party executes according to its own customary method. The Chinese company seals and signs. The American company signs. Nobody needs to adopt the other side's convention.
State the method in the execution clause. A line like "This Agreement shall be duly executed by each party in accordance with its respective formalities" handles the asymmetry cleanly.
If the counterparty insists you seal: make a seal and seal it. The question are image seals legally valid? is worth reading first, but in most cases, a professionally designed digital seal that clearly identifies your company satisfies the request. You can build one in the online seal generator in a few minutes.

What you should not do is argue about whether seals are necessary. If the counterparty's bank, legal team, or regulator expects a seal, the theoretical question of legal necessity is irrelevant — the practical question is whether the deal closes.

Digital contracts and electronic seals

The world of contracts is moving digital, and seals are following.

In China, electronic seals (电子签章) on digital contracts are legally recognized under the Electronic Signature Law and regulated through certified platforms. The seal is not a static image pasted into a PDF — it is a cryptographically signed object tied to a verified corporate identity. Electronic seals in China covers the platform landscape and what "certified" actually means.

Japan's Digital Agency has been pushing to reduce hanko dependency since 2020, and many contracts that once required a physical seal impression now accept electronic alternatives. Korea similarly recognizes electronic seals under its e-signature framework.

For companies outside these jurisdictions being asked to provide a sealed document to a counterparty who uses a digital contract platform, the situation is pragmatic: you typically need a seal image (transparent PNG at a legible resolution — here is how to make one) that gets placed on the PDF version of the contract. It is not a cryptographic seal; it is a visual mark that satisfies the counterparty's process. Whether that mark carries legal weight in your own jurisdiction is a separate question, but for closing the deal, it is usually what is needed.

Mistakes that actually cause problems

Most seal placement on contracts goes fine. The problems, when they happen, tend to cluster around a few recurring patterns.

Wrong seal. Chinese companies maintain separate seals for different purposes — the contract seal (合同专用章), the finance seal (财务专用章), the general seal (公章). Using the finance seal on a contract, or the general seal where the contract seal is expected, can result in a rejected document. Types of company seals explains the set and what each one is for.

Seal does not match the registered name. This is the most common substantive problem. The company has been through a name change, or the seal was made with a trade name rather than the registered name, or an English name appears on the seal that does not match the company's business licence. A counterparty's due diligence team will check, and the mismatch creates a question you will have to answer in writing.

Illegible impression. A faded, smudged, or undersized seal that cannot be read does not serve its identification purpose. If you are working with a digital seal, this is avoidable — the export is always clean. But if you are scanning a physical impression, the print-scan guide covers how to keep it legible through the reproduction process.

Sealing an unsigned document. In jurisdictions where both seal and signature are expected, a seal without an accompanying signature may be questioned. The seal authorizes the entity; the signature authorizes the individual. Sending one without the other leaves a gap.

Page-sealing only the first and last pages. If you are going to page-seal, do all pages. Skipping the middle pages — the ones with the actual obligations — is worse than not page-sealing at all, because it implies you page-sealed and then someone swapped the middle.

A practical sequence

If someone has asked you to seal a contract and you are not sure how to proceed:

Ask the counterparty what they need. Specifically: do they want the seal next to the signature, on every page, or both? Do they need a specific type of seal?
Check which seal to use. If your company has more than one, the contract seal is almost certainly the right one. When in doubt, someone asked you to seal a document walks through the decision.
Place the seal. The seal placement guide covers positioning and the PDF stamping guide covers the mechanical steps for digital documents.
If page-sealing is expected, seal every page, including the signature page. Do not skip pages.
Return the sealed copy in the format requested. Usually a PDF. Make sure the seal renders cleanly at the resolution the document will be viewed at — the size and resolution guide has the numbers.

Contracts are the one document type where seal impressions get scrutinized. The bank checking the contract file, the arbitrator reviewing the evidence, the counterparty's lawyer reading the execution page — they are all looking at your seal more carefully than anyone looks at a sealed invoice or a stamped receipt. That is not a reason to overthink it, but it is a reason to get the basics right.

If you do not have a company seal yet and a contract is waiting, the online seal generator will get you from nothing to a clean, properly formatted seal image in minutes. Start with the company seal design guide, pick the right shape and size, and export a transparent PNG. Then stamp the contract and close the deal.