Google has announced that the February security update for Android has already started rolling out to Nexus devices. The update brings about several bug fixes to 8 Nexus devices.
The devices that will be receiving the update on Android 6.0.1 Marshmallow are Google Nexus 6P, Nexus 5X, Nexus 6, Nexus 5 and Nexus 7 (2013). They will be updated to MMB29Q build.
The Nexus 9, Nexus Player and Pixel C will also be getting the patch and so will the Nexus 10. It will be getting the update on Android 5.1.1 however with LMY49G build number. The patch will fix 5 critical issues, four high-priority issues and a moderate bug.
While the update is rolling across these devices globally, it may take a while before they appear on your particular device. Although flashable factory images are available at the 2nd source link below, they will cause you to lose all information on your device and we suggest you wait for the OTA notification on your device.