So in Pittsburgh PA i run into this alot. Oak floors only stained and sealed around the edges of floor. Middle is raw. It looks as though it was done around a large area rug that was tacked into place. Of course rug is long gone and has been wall to wall carpet for years. Ive refinished these lots of times and the distinct square always stays. No matter what ive tried. Seems to be the best just to clear coat. But customers always want stain. I cant find anything online about this. Anyone else familiar with this?