This article discusses obviousness in patent law.

1. Summary

If an invention is an obvious combination of existing technology (prior art), the invention is not patentable. For the obviousness analysis, the existing technology is viewed through the lens of what patent law calls a person having ordinary skill in the art (PHOSITA). This theoretical PHOSITA understands all existing technology and has ordinary creativity. The KSR Supreme Court decision lists reasons that the PHOSITA would have to combine existing technology.

2. Non-obviousness Under 35 U.S.C. 103

One of the requirements to obtain a patent is that the invention be non-obvious. When the existing technology (prior art) can be combined in an obvious way to create an invention, the invention is not patentable due to obviousness.

35 U.S.C. 103 states:

A patent for a claimed invention may not be obtained, ... if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.

For 35 U.S.C. 103, the obvious determination is made with the state of the art at the time of the patent application filing. As technology advances, what is obvious today may have been non-obvious in the past.

3. Person Having Ordinary Skill in the Art

To determine non-obviousness, the prior art is viewed through a hypothetical person called a "person having ordinary skill in the art" (PHOSITA). In patent law, art essentially means technology and prior art is essentially prior technology. A PHOSITA understands all the relevant prior art and has ordinary creativity. The skills of the PHOSITA depend on the technology area of the invention. A PHOSITA in toy design may be very different than a PHOSITA in nuclear fusion. In very general terms, think of the PHOSITA as someone who has the entry-level skill set to enter the field of the invention but having complete knowledge and understanding of all the existing prior art. To learn about PHOSITA see MPEP 2141.03 Level of Ordinary Skill in the Art.

4. Rationales for Obviousness

The Supreme Court in KSR Int'l Co. v. Teleflex Inc. listed the rationales that would motivate a PHOSITA to combine aspects of various prior art references to determine that an invention is obvious. MPEP 2141 summarizes KSR as:

Examples of rationales that may support a conclusion of obviousness include:
(A) Combining prior art elements according to known methods to yield predictable results;
(B) Simple substitution of one known element for another to obtain predictable results;
(C) Use of known technique to improve similar devices (methods, or products) in the same way;
(D) Applying a known technique to a known device (method, or product) ready for improvement to yield predictable results;
(E) "Obvious to try" - choosing from a finite number of identified, predictable solutions, with a reasonable expectation of success;
(F) Known work in one field of endeavor may prompt variations of it for use in either the same field or a different one based on design incentives or other market forces if the variations are predictable to one of ordinary skill in the art;
(G) Some teaching, suggestion, or motivation in the prior art that would have led one of ordinary skill to modify the prior art reference or to combine prior art reference teachings to arrive at the claimed invention.

5. Secondary Considerations

Secondary considerations can be used to weigh toward non-obviousness. Secondary considerations include commercial success, copying by others, failure of others, licensing, long-felt but unsolved need, praise of others, skepticism of experts, and unexpected results. To learn more about secondary considerations see MPEP 716 and MPEP 2145

6. Analogous Art

Prior art must be analogous art to be considered during an obvious analysis. Analogous art is in the same field of endeavor or solving the same type of problem. To learn more about analogous art see MPEP 2141.01(a).

7. Fictitious Example

The following is a made-up example to illustrate obviousness in patent law. Assume the invention is a red car with a manual transmission. A first prior art reference discloses a green car with a manual transmission and a second prior art reference discloses a red car with an automatic transmission.

The invention is most likely to be found obvious since changing the color of the green car as disclosed by the first reference to red as disclosed by the second reference would create a red car with a manual transmission. This substitution of color may fall under the KSR rationale "simple substitution of one known element for another to obtain predictable results." In other words, creating the invention only requires substituting red paint for green paint.

8. Obvious to Combine Construction Equipment

In US patent number 3,055,280, Pavement Salvage patented a combination of an asphalt spreader/shaper and a radiant-heat burner into a single piece of construction equipment. Both the spreader/shaper and the radiant-heat burner had previously existed as separate pieces of construction equipment. The Supreme Court found that combining the asphalt spreader/shaper and radiant-heat burner was obvious and thus Pavement Salvage was not able to enforce their patent. See Anderson's-Black Rock, Inc. v. Pavement Salvage Co., 396 U.S. 57, 62-63, 163 USPQ 673, 675 (1969). To learn more about the Anderson's-Black Rock case, see the Wikipedia article.

9. Folding Treadmill Obvious

In US patent number 5,676,624, ICON Health & Fitness patented a folding treadmill with a gas spring. The gas spring assisted the treadmill to remain in the folded position. During a re-examination procedure at the USPTO, the USPTO found the treadmill obvious. ICON appealed the USPTO decision to the Federal Circuit. The Federal Circuit agreed with the USPTO that the 5,676,624 patent is obvious to the combination of a folding treadmill that lacked a gas spring and a folding bed with a gas spring. The result was that ICON lost the right to enforce the 5,676,624 patent. See In re ICON Health & Fitness, Inc., 496 F.3d 1374, 83 USPQ2d 1746 (Fed. Cir. 2007). Furthermore, MPEP 2143(I)(B) Example 5 discusses the ICON case.

10. To Learn More

Below are a few resources to learn more about obviousness.

- Read MPEP 2141 through MPEP 2145

- Read examples in MPEP 2143

- Review the USPTO patent examiner training at Examiner Training -> prior art rejections -> review 35 U.S.C. 103 training.