diff --git a/windows/security/threat-protection/microsoft-defender-atp/mac-whatsnew.md b/windows/security/threat-protection/microsoft-defender-atp/mac-whatsnew.md
index 34df1f32fc..081c1c88d8 100644
--- a/windows/security/threat-protection/microsoft-defender-atp/mac-whatsnew.md
+++ b/windows/security/threat-protection/microsoft-defender-atp/mac-whatsnew.md
@@ -19,6 +19,15 @@ ms.topic: conceptual
 
 # What's new in Microsoft Defender Advanced Threat Protection for Mac
 
+## 100.86.91
+
+> [!CAUTION]
+> To ensure the most complete protection for your macOS devices and in alignment with Apple stopping delivery of macOS native security updates to OS versions older than [current – 2], MDATP for Mac deployment and updates will no longer be supported on macOS Sierra [10.12]. MDATP for Mac updates and enhancements will be delivered to devices running versions Catalina [10.15], Mojave [10.14], and High Sierra [10.13]. 
+>
+> If you already have MDATP for Mac deployed to your Sierra [10.12] devices, please upgrade to the latest macOS version to eliminate risks of losing protection.
+
+- Performance improvements & bug fixes
+
 ## 100.83.73
 
 - Added more controls for IT administrators around [management of exclusions](mac-preferences.md#exclusion-merge-policy), [management of threat type settings](mac-preferences.md#threat-type-settings-merge-policy), and [disallowed threat actions](mac-preferences.md#disallowed-threat-actions)