Not like any Fenway seats I've seen. And last time I was there some areas still had the original seats.
The ones I think are the oldest are very similar to Yankee stadium seats. No curve to the back, and no arch to the top board. Sadly, I've come to believe my Fenway seat is actually from Yankee Stadium. I was told it was removed during a renovation in 70 or 71 and one of the construction guys bought it. That part I believe, since it was removed pretty roughly. But I can't find a reference to any 1970-71 renovations at Fenway. But Yankee Stadium did have renovations.
How it would have ended up in suburban Boston is a bit of a mystery.
Haven't taken a pic of it yet, so I swiped a couple off the interwebs..
Fenway
Yankee stadium
Mine has the same green color that's under the blue... Can't complain too much, it was super cheap in 83.