The Marshmallow sofa was designed in 1954 by Irving Harper. For decades the design of the Marshmallow sofa was attributed to George Nelson, as was the practice for designs coming out of George Nelson Associates, Inc. However, it was later revealed that many of the firm's designs were actually those of other designers working for the firm. John Pile, a designer who worked for George Nelson Associates, Inc. in the 1950s explained, "George's attitude was that it was okay for individual designers to be given credit in trade publications, but for the consumer world, the credit should always be to the firm, not the individual. He didn't always follow through on that policy though."
