ORDIUS TECHNOLOGIES

Verify if a PDF has been altered

Give every PDF a tamper-evident identity

PDF Authenticity · Edited PDFs · PDF Tampering · Invoice Fraud · Payment Redirection Fraud

Same document. Different outcome.

Payment-redirection fraud doesn't always require a fake invoice. It can be a real one, altered in transit.
Ordius gives you a way to verify the document's identity — before the payment is made.

1

Create

The issuer creates an official invoice and it's stamped with a unique, deterministic identity by Ordius.

OFFICIAL INVOICE
Supplier: Acme Supplies Co.
Invoice #: INV-2026-0047
Amount: $90,000.00
Bank: ABC Bank
Account: 1234 5678 9012
ORDIUS ID A3F9-7E2C-4B1D-9C6A...

The original document remains unchanged.

2

Share

The stamped invoice is sent through normal channels — by email, portal, link, or any channel.

OFFICIAL INVOICE
ORDIUS ID A3F9-7E2C-4B1D...

The document travels through normal channels, just like any other PDF.

3

Intercept & Modify

The document is intercepted by an attacker, who alters key details — such as bank account information or payment instructions.

MODIFIED INVOICE
Supplier: Acme Supplies Co.
Invoice #: INV-2026-0047
Amount: $90,000.00
Bank: Fraudster Bank
Account: 9876 5432 1098
ORDIUS ID B7C1-3D9E-6FA4-28BC...

The attacker changes the document without affecting how it looks at a glance.

4

Verify

The recipient re-checks the document's identity. Ordius compares the current document with the original identity.

VERIFY IDENTITY
× IDENTITY MISMATCH
Original ID A3F9-7E2C-4B1D-9C6A...
Current ID B7C1-3D9E-6FA4-28BC...

The document's identity is recomputed and verified at the byte level.

5

Payment Stopped

The mismatch is detected before payment is made. The fraud is stopped.

PAYMENT PREVENTED
×
FRAUDSTER

The payment never reaches the fraudster.

Create the identity
before distribution.
Verify the identity
before payment.
ORDIUS
Document integrity. Real-world protection.

Why choose Ordius?

FOR PDFS THAT CONTROL WHERE THE MONEY GOES

Ordius is designed around several core doctrines:

  • We don't normalize the document.
  • We don't strip its metadata.
  • We don't maintain metadata-exclusion rules.
  • We don't require a sidecar identity.
  • We don't require PKI to determine document integrity.
  • We don't rewrite the original bytes when stamping.
  • We don't store or retain the document on our servers after processing.
Create Identity Verify Document
ADDITIONAL LAYER OF PROTECTION

What Ordius verification establishes

01

SAME DOCUMENT

The document remains the same as when its identity was established.

02

SAME IDENTITY

The document carries the identity used to verify it.

03

ALTERATION DETECTED

Changes made after identity was established produce a mismatch.

Ordius verifies whether the document remains unchanged. It does not determine whether a change was authorized or legitimate.

What would you like to do today?

Create an Ordius ID for your document FREE

Free (10 per day)

Generate an Ordius Identity and embed an Ordius Block into your document.

Create Identity

Verify Ordius ID on your document FREE

Free (10 per day)

Confirm whether a document has remained unchanged.

Verify Document

Need to work with more documents?

Check out our available plans

Explore our paid plans to work with more documents per day

Check Pricing

Building with Ordius?

Identity creation, verification APIs, integration guides, authentication, examples, and complete documentation are available in the Ordius Developer Portal.

Developer Portal →

Frequently Asked Questions

What is an Ordius ID?

An Ordius ID is the durable digital identity assigned to a document. It uniquely identifies that document and allows its integrity to be verified at any point in its lifecycle.

What is an Ordius Block?

The Ordius Block is the verification block embedded into your document after identity creation. It contains the information required for Ordius to recognize and verify the document without changing the document's content.

Why do you have daily usage limits?

Ordius is free for personal use. Daily usage limits help protect the platform from automated abuse while ensuring that everyone can reliably create and verify document identities at no cost. If your needs exceed the free daily limits or require automated integration, additional usage plans are available.

Does Ordius store my documents?

No. Ordius does not archive or retain copies of your documents. Identity creation and verification operate only on the information necessary to establish and verify document integrity.

How does Ordius determine whether a document has changed?

Ordius verification is deterministic. When a document is verified, Ordius derives its identity from the document itself and compares it against the embedded Ordius Identity. If the document is a bit-for-bit identical copy of the original stamped document, it will produce the same Ordius Identity and verification succeeds. If any part of the document changes — even a single byte — the resulting identity changes, and verification will indicate that the document no longer matches its embedded identity.

Why did verification fail after I sent my document?

Some file-transfer, document-management, security, or collaboration systems may modify documents during transmission. For example, a system may normalize a document, rewrite its internal structure, remove metadata, or otherwise alter portions of the file. If this occurs, the received copy may no longer contain the Ordius Block or may no longer correspond to the identity originally assigned to the document, and verification may fail. Your original stamped document in your local storage is not affected by this. If the original copy remains intact on your device, it still contains its Ordius Block. You can resend that original copy using a transport method that preserves the document. In our testing, Gmail successfully preserved Ordius-stamped PDFs through attachment delivery.