The decision is a significant reversal of fortunes for Apple, which was initially awarded north of $1 billion, before seeing its damages eroded to $548 million and finally to just under $400 million with successive appeals by Samsung's lawyers.

In the Supreme Court's unanimous decision, written by Justice Sonia Sotomayor, it found that copyright law does not allow Apple to claim damages for the entirety of Samsung's smartphone profits, only the portions directly related to the patents that Samsung allegedly infringed, which the law calls "articles of manufacture." A lower court had ruled that because the components of a smartphone are not sold separately to consumers, Samsung should have to pay damages based on its overall smartphone profits.

"In the case of a design for a single-component product, such as a dinner plate, the product is the 'article of manufacture' to which the design has been applied," Justice Sotomayor wrote. "In the case of a design for a multicomponent product, such as a kitchen oven, identifying the 'article of manufacture' to which the design has been applied is a more difficult task."

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