In the case of Sakraida v. AG Pro, Inc., 1975, the United States Supreme Court ruled in favor of Henry A. Sakraida and reversed a previous decision by the Fifth Circuit Court that had upheld a patent owned by AG Pro, Inc. The patent was for an innovative water-flushing system used to clean out dairy barns more efficiently than traditional methods. The Supreme Court found that while this invention may have been useful and time-saving for farmers, it did not meet the standard of non-obviousness required for patent protection under U.S law because it merely combined existing elements with no change in their respective functions - essentially arranging old elements with each performing its known function is usually not enough to achieve a new or different result sufficient to make such arrangement patentable as an "invention". Therefore, they concluded that AG Pro's patented design was obvious and thus ineligible for legal protection.

In the dissenting opinion for Sakraida v. AG Pro, Inc., Justice William Rehnquist argued that the majority's decision to invalidate a patent on grounds of obviousness was incorrect. He contended that this ruling disregarded precedent set by previous cases which had established standards for determining whether an invention is non-obvious and therefore patentable. According to him, these standards required consideration of secondary factors such as commercial success and long-felt but unsolved needs in addition to scientific or technological advances made by the invention. The majority's focus solely on whether the patented device combined previously known elements in an obvious way failed to consider these other important aspects of non-obviousness, he claimed. Furthermore, he criticized their reliance on hindsight bias when assessing if combinations were obvious at the time they were made.