I can tell you what it isn't........it is NOT 'Fireglow' :-) Leaf shape and coloration are not at all similar to that cultivar.

As to what it may be, I'd direct you to this recent thread on J. maple identification. I feel like I am beating a dead horse by repeating it so often, but it is virtually impossible to identify a specific cultivar of Japanese maple with any degree of accuracy. Those who offer suggestions as to specific cultivars are only guessing.

I have Fireglow and that's not it. :)

You might never know for sure, but I understand the curiosity and the need to have a pretty good guess.

Summer color isn't all that helpful, but it's something. Collect info on leaf size, leaf shape, spring color, and fall color (photos would help), then come back or post in one of the facebook or JM forums online. There are lots of people who enjoy guessing.

Some time spent with Vertrees' book on Japanese Maples would also be a good investment, in case you haven't already.

Guesses are just that - simply guesses ;-)) And since there is unlikely to be true JM experts lurking on other forums or social media, the guesses could be all over the place and not get you any closer to knowing exactly what you have.

My suggestion to those who have unnamed or mislabeled JM's is just to enjoy what you have and call it Fred. Or George :-) Or whatever name you like for your own purposes. FWIW, I've never encountered a single Japanese maple of any variety that didn't have its own appeal regardless of the name assigned to it.

Thanks everyone for your comments. It is a nice maple, doing well in the garden, and as I realized is not Fireglow but thought, perhaps, it might be an obvious variety or one that might be recognizable.