The certification is based on the globally recognized Ghent PDF Output Suite which was developed to help testing PDF/X-4 compliancy of PDF output workflows. The Ghent PDF Output Suite 5.0 consists of several dozen patches each testing a specific aspect of the PDF/X-4 standard. The GWG has put together a great number of these patches into six merged test pages.

This test file is fully PDF/X-4 compliant and contains only valid PDF/X-4 features which represents what could be part of every regular PDF/X-4 print production file.

The pages of the Ghent PDF Output Suite 5.0 are grouped into two conformance levels:

• Conformance Level 1: pages 1–4 which includes CMYK and Spot color tests
• Conformance Level 1+2: pages 1–4 AND pages 5–6 which includes ICC based color tests

Conformance Level 2 involves color management and is therefore more demanding. Full details are available here.