[Rajdeep_442]

I am on Marshmallow 6.01 having a Samsung Galaxy Note Edge. Since I never use wifi, I have disabled it in Location and wifi settings. However, when I peruse through my battery history, it shows that my WIFI is on. I don't know if it is Marshmallow bug, eating into my battery .This trick has helped me resolve this issue.
~ I go to locations and put it on. I enable GPS only [ device ] and then quickly disable location.
~ Following this, I turn my phone into Airplane Mode and then disable it after a minute.
Thereafter, I see that WIFI is no longer reflected in my battery history.
Alternately, I have reset Network settings and rebooted my device. I don't know if this works or not.
So far I been able to resolve this issue using the above. Can someone let me know, why does wifi turn on by itself without any user intervention? Is it a Marshmallow bug which we have to endure ?
Can someone let me know a permanent solution for this.

[Rajdeep_442]

The answer lies here :
PSA: Option to disable background Wi-Fi and Bluetooth location scanning have moved in Android 6.0 Marshmallow
"With Android 6.0 Marshmallow, Google has tweaked and moved things around. In addition to Wi-Fi, Google is now also allowing apps to use Bluetooth to scan for networks. This means that even if you have Wi-Fi and Bluetooth turned off, your Android device running Marshmallow will still use both Wi-Fi and Bluetooth to scan for networks and improve location accuracy."
" This should not really be that big of a deal since you can always disable the background scanning of Wi-Fi and Bluetooth networks from under Advanced Wi-Fi Settings. Right? Wrong. Google has moved the options related to background scanning of Wi-Fi and Bluetooth networks under ‘Scanning’ in Locations in Android 6.0. Since these features are used to improve the location accuracy, it does make sense for Google to move them under Locations."
I just followed the instructions here as well as reset " Network Settings" followed by a restart.
Wifi is no longer reflected in my battery history and this should show a positive improvement in my battery performance.

[B. Diddy]

Glad you found the answer! This is relatively common issue.