I have noticed a disproportionate amount of ceph.io mail lands up in spam.  Checking the headers, I see: Return-Path: <ceph-users-bounces@ceph.io> X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on box2.fast.za.net X-Spam-Flag: YES X-Spam-Level: ******* X-Spam-Status: Yes, score=7.2 required=5.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,DMARC_FAIL_REJECT,FREEMAIL_FROM,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=no autolearn_force=no version=3.4.4 X-Spam-Report: * -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% * [score: 0.0000] * -0.1 SPF_PASS SPF check passed * 10 DMARC_FAIL_REJECT DMARC check failed (p=reject) * 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record * 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail * provider * [caduceus42[at]aol.com] * 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily * valid * -0.0 T_SCC_BODY_TEXT_LINE No description available. * 0.1 DKIM_INVALID DKIM or DK signature exists, but is not valid * -1.0 MAILING_LIST_MULTI Multiple indicators imply a widely-seen list * manager X-Spam-Score: 7.2 Why is this? DKIM invalid?