Does the auction say what the medallion says? Without that or "raising" an etch, it's nigh impossible. That said, it looks like a Disston. It's after 1890 because of the domed nuts. 3 bolts--either it is a shorter panel saw, perhaps 20" or less or else it was a house branded saw. Often the hardware store saws had less bolts, poorly shaped handles, or both. This one has a nice handle, which is why I would think it is a shorter than 26" saw. Most panel saws had less bolts than the larger versions.
It's fairly fine pitched [number of teeth per inch is on the higher end]. The blade appears like it would clean up well.
Take care, Mike
Wenzloff & Sons Sawmakers