This scroll did not pass my inspection. It has a minor watermark in the paper of the painting (near the top left of the painting in the background). This one really blends in with the antique style of the painting (some people like this because it makes it look aged).

Many people (including the artists) believe that such watermarks are a natural and necessary part of this kind of watercolor paintings. Others even feel that is it proof of the handmade nature of the artwork. I still have to discount it to avoid any misunderstandings.