If memor serves correctly, WNEW 1130 IDed at the TOH with 'WNEW Metromedia Radio, New York', for years. This was decades ago.
With, as Scott Fybush says, the rules as unclear as they are, the feeling here is that if there's no intent to defraud or mislead, things are fine.
To me, a more heinous situation would be the blatant burial of a substandard city-of-license in the bellowing blaze of a more prestigious city. Most of us have heard a few.
There's far more deceit there. And it's purposeful, scheduled chicanery, too -- almost 9000 times a year. But then again, it seems the only people who rightfully would have a pursuable gripe would be some sort of dignitaries or watchdogs who actually lived in the community that's being given the finger every hour.
Re WNEW again:
Of course, there was the occasional instance at news time where the mischievous Gene Klavan, backtiming like he had to, would crank up the reverb and send 'W-W-N-W-N-EW-nnn -N-N-W!!!-W-E-W Metro (W) metro-Media-metro-media-media-New Yorknewyorknewywork (gish-gish GISHHHHH)' over air, splashing onto WHLI 1100 and WLIB 1190. Then he'd key off and just stop the whole racket cold for the TOH
'beep'.
One morning, man, the poor newsman at this legendary conservative MoR station, hearing this abomination through his erphones, just LOST it. I expect a memo came down to the news anchors to get the cue and the beep from some place other than 'that goofball down the hall'.