Canon EOS R3 Advanced User's Manual page 961

Note
During playback, you can check whether IPTC information was added.
You can use Digital Photo Professional (EOS software) to check IPTC information
in images.
IPTC information registered to the camera is not erased if you select [ : Clear all
Custom Func. (C.Fn)] ( ), but the setting changes to [Disable].
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