How Trellis Receipt PDFs are Protected

This article explains how Trellis receipt PDFs are locked from editing, digitally signed, and encrypted to ensure they remain secure and compliant with industry best practices.

To protect donors and ensure receipts meet best practices for digital security, we’ve added multiple layers of protection to all PDF receipts generated through our platform. These changes help prevent tampering, unauthorized changes, and ensure long-term integrity.

What's Changed?

We’ve applied a series of security steps to every donation receipt PDF:

• Read-Only Format (PDF/A): The file is saved in a special format meant for long-term storage. This format prevents editing while keeping the file easy to open and view.

• Cryptographic Signature: We add a secure digital signature to each PDF. If someone tries to change the receipt, the signature will break, proving it’s been tampered with.

• Editing Locked (But Viewing Open): The PDF is encrypted with a password that blocks editing tools. You won’t need a password to open and view your receipt, but no one can modify it without access to our internal encryption key.

• Flattened Content: All the information in the PDF is embedded in a way that prevents text from being altered or copied into form fields.

Why This Matters

Making receipts secure isn’t just about following the rules—it’s about protecting your organization, your donors, and maintaining trust.

Secure, tamper-proof receipts:

• Prevent unauthorized changes to donation amounts or details.

• Ensure consistency in audit trails and financial records.

• Protect against fraud or misuse.

• Provide assurance to donors that their records are authentic.

• Comply with guidelines from regulators like the Canada Revenue Agency (CRA), which require digital receipts to:

  • Be read-only and protected from edits.

  • Include all required donation information.

  • Be encrypted and signed, ideally under the control of the issuing organization.

  • Be safely shareable by email.

Our new system ensures all of this is in place, giving you peace of mind and keeping your receipts secure and compliant.