tl;dr: Google Play is threatening to remove AnkiDroid (10M+ installs) from the store on September 11 unless it removes its Open Collective donation link, arguing donations must go to a "tax-exempt organization." AnkiDroid's fiscal host, Open Source Collective, provided an IRS determination letter confirming 501(c)(6) tax-exempt status, but Google support has repeatedly rejected it without explaining why 501(c)(6) doesn't qualify (the policy doesn't specify 501(c)(3)). The team is removing the donation link under protest and asking for help escalating to someone inside Google.