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The ONIX standard is now defined by ONIX 3.0 but ONIX 2.1 remains in use
ONIX 2.1 is no longer a supported standard.
As of early 2017 the ONIX 2.1 will not be further updated in any way and past Code List Issue 36 (released January 2017). It is the final code list for this version. But being unsupported does not mean it is not used. ONIX 2.1 may remain in use for however long two companies choose to continue to use the standardtrade data using that version.
In North America ONIX 2.1 continues to be used for almost all data physical book metadata transfers and retailers are having difficulty finding enough ONIX 3.0 suppliers to begin to program to accept it.
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ONIX 3.0 users should update their code lists for Issue 37 and beyond. ONIX 2.1 users should use code list Issue 36 going forward.
If you need help, contact biblio@booknetcanada.ca.
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