Last couple of weeks I had a discussion with David about this subject on bug 24544.

Please see https://bugs.koha-community.org/bugzilla3/show_bug.cgi?id=24544

What do you think? If your authority, biblio or item has a PID, should we save it in MARC too? Noting that MARC is just a representation or view of your data. We already have a biblio_metadata table that allows for more. What if we already had multiple views? If you can, you are welcome to contribute to that discussion on the bug report.

Thanks,

Marcel