How do mailing lists affect authentication?

Mailing lists usually remail rather than simply forward. They often modify the message by adding subject tags like \[List Name\] inserting footers rewriting headers or altering MIME structure. These changes break DKIM because the signed content no longer matches and they break SPF because the list’s server becomes the new sending IP. Without ARC both SPF and DKIM fail which causes DMARC to fail.