Concurrent use proceedings under trademark law are fact-intensive proceedings. They are also relatively rare. In SOUTHWESTERN MANAGEMENT, INC. v. OCINOMLED, LTD., No. 2015-1939 (Fed. Cir. June 15, 2016), the Federal Circuit heard oral argument with respect to a concurrent use proceeding over the mark –DELMONICO’S– for restaurant services.
You can listen to the oral argument [here].
The Rule 36 Judgment is available [here].
You can read the precedential TTAB decision [here].