Increased bounce rates specifically from Apple Mail can arise from various factors. 'Unclassified' bounces need investigation to uncover specific bounce codes. Apple's Mail Privacy Protection can inflate open rates and skew engagement metrics. Damaged sender reputation, stemming from poor sending practices, spam triggers, or invalid addresses, is a key contributor. Authentication issues (SPF, DKIM, DMARC), stricter DMARC policies, and sending to old or unengaged lists are also significant causes. Email content, sending infrastructure for transactional emails, and use of custom domain all play a role. Monitoring bounce codes, practicing list hygiene, email testing, and following best practices are essential for resolution.