Stamping a chop on a book shows who it belongs to; a studio name seal stamped on an old calligraphic work may mean "this work has been in my collection" or "I authenticate this work as genuine."
在書末蓋方印，表示為某人藏書；在古字畫上鈐蓋齋館名號，有的明示「此物曾歸我所有」，有的則意在宣告「我某人鑑定該作品為真跡無誤」。