Judge Markey famously wrote “Only God works from nothing. Man must work with old elements.” Howard T. Markey, Why Not the Statute?, 65 J. PAT. OFF. SOC’Y 331, 334 (1983). His point was simple and well taken—every invention is a combination of something old. An obviousness argument must be more than the arbitrary combination of references that each disclose separate elements of the claim. It’s not about the ingredients; the magic is in the final combination.

But how does the law of obviousness address these philosophical views of innovation? The landmark KSR v. Teleflex case laid the groundwork for combination claims as follows: “The combination of familiar elements according to known methods is likely to be obvious when it does no more than yield predictable results.” KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 407, 415 (2007).

Case law would later focus on the word “predictable.” That is, inventions that yield predictable results are far less likely to be considered patentable. Combining yellow and blue will predictably yield green. Adding an acid to a solution will lower its pH. These are not patentable inventions because one of ordinary skill would have had common sense and foresee these results. But inventions that yield unexpected results are more likely to overcome these arguments of predictability.

Unexpected results are commonly used in chemical or pharmaceutical patents to illustrate that the combination of known elements yields something that was not predictable and therefore nonobvious. Unexpected results often come in the form of data that shows (1) a sharp increase or decline at a particular data point, (2) the unexpected efficacy of the claimed combination, or (3) synergistic results from the individual elements. The key is to show that the results of the claimed combination were not only beneficial, but also unexpected as compared to what would have been predictable from the individual elements outside of the combination. Unexpected results should be described in the specification in the form of charts, graphs, and examples with a clear discussion of why the results are unexpected and what the patentee would have normally expected from the claimed combination.

The crux of an unexpected results argument is that the combination of prior art would not have been obvious because the results were not predictable. The argument attacks the combination of references rather than the disclosure of each reference. There are other ways to rebut a combination of references, but these methods are not as powerful. For example, references should not be combined if they teach away from one another; or if adding “Reference B” would render the device in “Reference A” unsatisfactory for its intended purpose. But these arguments are reference-specific and can be easily dodged if the obviousness argument uses a new reference. An unexpected results argument focuses on the claim elements themselves and why the combination would not have been obvious due to the unpredictable results that were obtained.

Make no mistake, unexpected results can be burdensome to prove. It can be costly and time consuming to provide experimental data in a patent application. And patent applicants are in a “race to the Patent Office” mindset to obtain the earliest possible priority date for their patent. However, for chemical and pharmaceutical patents, unexpected results can provide the strongest basis for overcoming an obviousness argument either before the Patent Office or in response to an invalidity challenge in litigation