If they were violating the rules of conduct on a ranked server, you can report them. See the following page for more information: https://help.ea.com/article/bf3-rules-of-conduct [help.ea.com]
January 2014 - last edited January 2014 by inSmithereens
January 2014 - last edited January 2014
If you don't like rented servers do a search via the server browser for Official DICE or EA servers and then check the server owner to ensure it is DICE or EA (some rented servers try to impersonate official ones to get players).
Rented servers have been going on since Battlefield started on PC and was a resounding success on console in BF3 so I am confident that EA will not do away with rented servers.
Battlefield Player on PC, Xbox One, PS4, Xbox 360, PS3
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SWTOR Player on the Harbinger and Red Eclipse