Most sail makers put the boat manufacturer's logo at the top of the sail - it's a pretty standard practice. I had custom sails built for a Nacra I owned some time ago and they had the "N" logo at the top. Monohull sailboats typically don't have the same sail manufacturer restrictions that we do in the catamarans. It's standard to get the proper logo at the top of the sail regardless of who is building the sail.