I am trying to find a replacement threshold for my back door, but I haven't a clue who the manufacturer is. There is a logo etched in the lower right corner of the glass; however, I cannot figure out who's logo it is. They're hard to photograph, but I finally got a decent image of the etch. If anybody can point me at the manufacturer, that would be greatly appreciated!
That logo will be the manufacturer of the insulated glazing unit (just the glass).
Door companies will use IGUs + Doors and pieces from various manufacturers to create a door that is then sold to the consumer. In my experience the door manufacturers put their mark on the top edge of the door or via a metal plate on one of the width edges.