org.apache.poi.openxml4j.opc.PackageRelationshipTypes has the following
remark:
/**
* Core properties relationship type.
*
* <p>
* The standard specifies a source relations ship for the Core File
Properties part as follows:
* <code>
http://schemas.openxmlformats.org/officedocument/2006/relationships/metadata/core-properties
.</code>
* </p>
* <p>
* Office uses the following source relationship for the Core File
Properties part:
* <code>
http://schemas.openxmlformats.org/package/2006/relationships/metadata/core-properties
.</code>
* </p>
* See 2.1.33 Part 1 Section 15.2.11.1, Core File Properties Part in
[MS-OE376].pdf
*/
This may have been true in an older version of ECMA-376 but the latest
edition (dated December 2012) specifies the same schema as the Office one.
ECMA-376 Part 2 Annex F Table F-1 lists the namespace URI as "
http://schemas.openxmlformats.org/package/2006/metadata/core-properties".
Are there any known XLSX exporters that use the non-office schema?
Unfortunately I didn't find a comment in the source about it.