One document.
More than one thing to check.
Imagine a quotation forwarded in a chat: a company logo, a clear signature and a QR code that opens immediately. These help you follow up, but questions remain. Who issued it? Does it match what was agreed? Is this still the version to use?
This guide takes a step-by-step approach, matching evidence to the question. It is for anyone receiving quotations, certificates or everyday business documents, whether checking them regularly or occasionally.
Who issued it?
The organization, signatory and a channel for confirmation.
Do the details match?
Whether the received version matches the source evidence.
Is it still valid for this purpose?
The current version, cancellations and conditions of use.
Confidence begins with knowing
what you have checked—and what you have not.
Six steps you can take now
- Start with how the document will be used
Reading for context is different from approving work or confirming an agreement. Choose a level of checking that reflects the consequences of that use. - Verify the issuer through a known channel
Read the full organization name. If you need to call or email, use contact details from a known official website, rather than relying only on the file you are questioning. - Compare the document number, version and date
One number may cover several versions. If a document says revised, canceled or superseded, ask which version applies to the matter you are handling. - Check the substance against the agreement
Check the parties, scope, terms and schedule. Matching a company name and document number is not enough on its own. - Check the file and signature where supported
For a digitally signed PDF, use a compatible tool to inspect the signer, certificate and any reported changes. Read the tool’s warnings as well. [1] - Keep the original and the confirmation context
Keep the issuer’s file with the date and channel used to confirm it. When forwarding it, explain which version it is, what it is for and what you have checked.
Before uploading a file to an online checker, review its policies and your permission to share the document, especially if it contains customer, employee or nonpublic information.
Explore a document, one detail at a time
Select the numbered points to see what each detail helps you check. This is an educational example with no real registered document number.
Select points 1–4 to read more. Learning example, not a real document.
ILLUSTRATIVE SAMPLESAMPLE
This example has no real verification result.
Issuer and official contact
Read the full company name and compare the contact details with a known official website. If in doubt, use that channel directly.
A matching name or logo alone is not enough.QR codes, watermarks and signatures
What does each one prove?
Having several features on a page does not automatically provide every type of evidence. Understand each feature’s role before interpreting the result.
| Feature | What it helps with | What to check next |
|---|---|---|
| Watermarks and signature images | Identify the format and information shown on the document. | Images can be copied. Visual inspection alone does not establish the original file or the signer’s intent. |
| QR codes and document registers | Open a source for comparing numbers, versions and status within the information the system makes available. | Check the destination and details yourself. A QR code linked to a genuine record may be copied onto an altered file. |
| File hashes | Compare a value calculated from the file with a trusted reference value. [3] | The reference must genuinely come from the issuer. A hash written inside the same file does not, by itself, establish who issued it. |
| Digital signatures | When properly implemented and validated, help check the origin and integrity of signed data. [4] | Read the certificate status and complete result. Technical validation does not certify every statement in the document as true. [1] |
A digital signature is a form of electronic signature that uses cryptography. It is more than the signature image you see on a PDF, so each case requires evidence and context appropriate to the method used. [1]
Terms you may see in a result
- Document register
- The issuer’s record of documents, such as number, version, date and status. Recipients may be able to view only part of that information.
- Hash
- A value calculated from data using a hash function. It can help check file integrity when compared with a trusted reference produced using the same method.
- Digital certificate
- Information linking an identity to a key used to verify a signature. Its issuer and current status also need to be considered.
- Timestamp
- Evidence about a time associated with electronic data, according to the service used. It differs from a date simply typed into a document.
Read the result carefully
then decide what to do next
“Record found,” “not found” and “unable to verify” mean different things. A useful result should state its scope, the time of the check and where to follow up if anything remains unclear.
Explore hypothetical scenarios. This does not search a document database.
Continue by comparing details and status
The issuer, number, version and date should match the document received. This result confirms a register entry; it does not check every byte of the forwarded file.
Example: a valid QR code on altered content
Someone could copy a QR code from one document onto another file. Scanning may still open a genuine record. Compare the key content and version with the issuer’s evidence; if an original digitally signed file is available, check it too. Finding a record and checking a file are separate steps.
Example: a genuine document that has been superseded
A properly issued document may no longer be the version to rely on today. Asking for the current version helps avoid errors from repeatedly forwarded old files, while still considering the terms and intended use.
Put it to work in your team
without adding unnecessary steps
Start with one document type your team uses often. Decide who checks it, what to check and whom to ask if details differ. Use the checklist below as a reminder, adapting it to your team’s risks and responsibilities.
For an organization, useful lessons come from how long it takes to find the latest version, which information gets requested repeatedly and where recipients remain confused. Use that evidence to improve the process, without expecting one technology to solve everything.
Share the document number, date and question through info@th-tiis.com or 02-681-9799 Our team will review the details relevant to your question. Hide unrelated personal information before sharing any supporting images.
These details inform how we develop TIMS to support the TIIS team. Learn more in our working principles and the technology behind our service or Contact the team For inquiries about related services
Frequently asked questions
If a QR code opens, does that prove the document is genuine?
You still need to check who runs the website, whether the record matches your document and what the service verifies. Opening a link alone does not validate the file you received.
Can I validate a digital signature from a photo or scanned PDF?
A scan captures an image; it does not automatically preserve the original file’s digital signature structure. For technical validation, request the signed electronic original from the issuer.
Does a valid signature mean all the content is correct?
Technical validation has a defined scope, such as the signer and changes to the data. You still need to assess the substance, authority and context of use. [1]
What if no record is found?
Recheck spelling, the document number, issuer and service scope, then contact the issuer officially. A missing search result alone does not prove a document is fake.
Where can I learn more or find verification tools?
ETDA explains electronic signatures and provides TEDA Web Validation for supported file types and formats. Review the terms and your permission to submit a file before using the service. [2]
Read the original sources
Primary sources supporting the technical explanations; links and content were reviewed on 27 September 2026. The scenarios and checklist were prepared by TIIS for learning purposes.
- [1] ETDA — e-Signature and Digital Signature questions ↗Signature types, certificates and the scope of validation
- [2] ETDA — TEDA Web Validation ↗Supported document types and validation scope
- [3] NIST CSRC — Hash function ↗Hash functions and their basic properties
- [4] NIST CSRC — Digital signature ↗Checking data origin and integrity with digital signatures
This is general educational information about reading and checking documents. Specific requirements and legal effects depend on the document, the facts and the applicable rules.