What is the “Old Combination” principle in patent law?

The “Old Combination” principle was a former doctrine in patent law that suggested an inventor who improved only one element of an old combination should not be able to patent the entire combination. However, this principle is no longer valid in modern patent law.

As stated in MPEP 2173.05(j): “A CLAIM SHOULD NOT BE REJECTED ON THE GROUND OF OLD COMBINATION. With the passage of the 1952 Patent Act, the courts and the Board have taken the view that a rejection based on the principle of old combination is NO LONGER VALID.”

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Topics: MPEP 2100 - Patentability, MPEP 2173.05(J) - Old Combination, Patent Law, Patent Procedure
Tags: 1952 Patent Act, Lincoln Engineering, Old Combination, patent claims