ONIX 3.1.1 allows the expression of EU-style opt-outs from the copyright exception applying to non-research uses of text and data mining (eg for training large language models) with collateral material. It has been possible to express such opt-outs on product content for some time, but revision 1 extends this to long descriptions, tables of contents, reading guides, cover images and other resources which are included in or linked from Block 2 of ONIX. The other additions enable identifiers for literary prizes, and a textual expression of the copyright statement in addition to the structured copyright owner data.

Version 3.1.1 is fully backwards compatible with the previous 3.1 release – any correctly-constructed ONIX 3.1 remains valid under 3.1.1, and most ONIX 3.0 files can be easily converted to 3.1.