Contact sync shares profile with matching contacts

Substack now discloses that it shares account identifiers, such as email addresses and usernames, with trusted industry child safety organizations to detect and prevent online child sexual exploitation and abuse. The policy also establishes that Substack will respond to privacy rights requests within one month, or up to three months for complex requests, providing more certainty about response timelines. Additionally, the policy clarifies that direct message recipients may retain messages even if you request deletion or delete your account, which is now explicitly stated rather than implied.

The updated policy no longer commits to responding to privacy rights requests within one month or within three months for complex requests. This removes a procedural timeline that previously bound Substack's response obligations. Additionally, the explicit disclosure that Substack shares account identifiers with child safety consortia to detect online child sexual exploitation has been removed from the policy, though the practice itself is not stated to have ended. The direct message retention language is now framed more directly: recipients may retain messages even if you request deletion or close your account.