Patents: What Makes an Invention Nonobvious? | AIChE

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Patents: What Makes an Invention Nonobvious?


This article is based on a chapter of the author’s latest book, First to File: Patents for Today’s Scientist and Engineer, published in 2014 by the AIChE-Wiley imprint.

In addition to being novel, an invention must be nonobvious to qualify for a patent. Learn strategies that have and can be used to qualify your invention as nonobvious.

An invention must be both novel and nonobvious to qualify for a patent. Of these two requirements, novelty is the threshold: An invention must be novel before nonobviousness can be considered. Establishing novelty was the topic of “Patents: Crossing the Novelty Threshold,” which was published in the Nov. 2015 issue of CEP (pp. 38–46).

As for nonobviousness, there is no clear and straight-forward definition, which has made nonobviousness the subject of debate ever since the first patent law was enacted. The patent courts agree that an invention must be either obvious or nonobvious to a hypothetical “person having ordinary skill in the art,” but the courts have not agreed upon this person’s credentials. Neither advanced academic degrees nor a certain number of years of working experience are by themselves determining factors. Indeed, too much education or experience can disqualify a person as easily as too little.

Nevertheless, some guidelines for assessing non-obviousness are necessary. This article sets forth these guidelines, by showing the common reactions of inventors when told their inventions are obvious and the ways in which the U.S. Patent and Trademark Office (USPTO) and the courts have responded.

“Isn’t every invention a combination of old elements?”

Every invention can be broken down into parts and subparts until it is reduced to a combination of elements that are already known (i.e., prior art). Nevertheless, there are several ways in which combinations of known elements can be shown to be nonobvious.

The synergistic effect. One way to show that an invention made up of a combination of old elements is non-obvious is to show that the combination displays a synergistic effect. Bayer Crop Science made such a showing in obtaining its Patent No. 8,524,634 (1). The patent claims a method for protecting agricultural crops against insects and other pests by treating the crops or their seeds with a combination of clothianidin and a synthetic pyrethroid. Both clothianidin and synthetic pyrethroids were already used separately as insecticides, but they had never been used as a combination.

In its field tests, Bayer raised corn plants from seeds that had been treated with clothianidin, tefluthrin (a synthetic pyrethroid), or a combination of the two, at various application rates (grams of insecticide per kilogram of seed), and then infested the plants with black cutworm, a common crop pest. After an appropriate growing time, the plants were evaluated for stand reduction (percent loss of the plants) and percent control (of the cutworm), both relative to plots of the same plants grown from untreated seeds. Plants grown from seeds treated with a combination of the two insecticides had a lower stand reduction and higher percent control than those grown from seeds treated with just one of the insecticides at the same total application rate. These results established the synergistic effect of using a combination of insecticides and hence the combination’s nonobviousness.

Adding a new function to an old element. When synergism cannot be shown, a combination of old elements can still be nonobvious if one of the components in the combination performs a different function than it did either by itself or in a previously disclosed combination.

This argument was used in obtaining Patent No. 7,713,133 (2), which claims a tennis court substrate encrusted with particles of waste glass of a specified size range. The waste glass helps maintain the quality of the surface and eliminates the need for yearly resurfacing. The USPTO initially rejected the claims, citing an earlier patent that disclosed the use of particles of waste glass as a filler for roadway paving. The inventor responded by arguing that the glass particles perform a different function when they are on the surface of the substrate than they do as a filler; and, neither the existing knowledge of paving materials nor the earlier patent’s description of the use of glass particles as a filler would provide sufficient reason for a paving contractor to adhere the particles to the surface rather than to mix them in with the substrate material. The argument succeeded at the Appeals Board (3), and the patent was granted.

“Would a rocket scientist consult a veterinarian (to provide a missing element)?”

Most likely not. For inventions that combine old elements without displaying synergism or changing the functions of the elements, the argument of unrelated sources can be used, i.e., the sources are not in similar or related areas of technology, or, in legal terms, the “arts” in which the various elements were originally found are not “analogous” to each other. One issue with this argument is that the USPTO interprets the term “analogous” broadly. Inventions can nevertheless be nonobvious if the original sources of its elements are sufficiently removed from each other (non-analogous).

One such invention is claimed in Anchor Holdings’ Patent No. 8,224,669 (4), which is directed to a healthcare management system that patients and clinicians can use to help manage diabetes and other chronic diseases. The system as claimed includes a database that contains medical, education, exercise, and diet information for managing the disease and allows both the patient and the clinician to access the information and add to it. The patient can indicate the reading materials the patient has read from a list provided by the clinician and the clinician is alerted when the patient has read all of the materials.

When Anchor Holdings applied for the patent, the examiner rejected the application over a combination of three earlier patents. Two of the patents were directed to systems for monitoring chronic diseases and the third was directed to a system for collecting, processing, and distributing information to promote driver safety for use by automobile insurance carriers. The examiner cited the third patent in reference to the component of Anchor Holdings’ invention that enables the patient to report to the clinician which instructional materials have been read.

Anchor Holdings appealed the rejection, arguing that the field of technology of the third patent was non-analogous to those of the first two patents and the Anchor Holdings invention. The Appeals Board agreed with Anchor Holdings, noting that “[t]he analogous-art test requires a showing that a reference is either in the field of the applicant’s endeavor or is reasonably pertinent to the problem with which the inventor was concerned in order to rely on that reference as a basis for rejection,” and that the examiner had shown neither (5).

“But nobody knew what the problem was before I came along!”

Even when the elements of a combination perform the same function that they were known to perform individually and were initially found in analogous arts, the combination can still be nonobvious if the invention lies in the discovery of a problem, or of the cause or source of a known problem. An obvious solution can be a patentable invention if the problem itself (or its cause or source) is not obvious.

Aktiebolaget Hassle was granted two patents (6, 7) once it showed that it had discovered the cause of a problem. The patents — Patent Nos. 4,786,505 and 4,853,230 — claim formulations for omeprazole, the active ingredient in Prilosec, a drug used to treat various diseases caused by excess stomach acid. Omeprazole is most effective in an alkaline environment and was known to degrade in acidic media. On its way to the small intestine, which is alkaline, the drug must pass through the stomach, whose acidic environment is known to degrade the drug. Encasing the drug in an enteric coating prevented much of this degradation, but an acidic substance in the coating itself degraded the drug, particularly during storage. Drug companies tried to solve this problem by adding alkaline compounds to the drug core, but the degradation persisted.

The inventors in the two Aktiebolaget patents added a protective subcoating between the drug core and the enteric coating. Since omeprazole is known to be susceptible to water degradation, there was a risk that if the subcoating were water-soluble, it might expose the drug core to degradation from acidic gastric juices. To the inventors’ surprise, however, a subcoating containing water-soluble substances not only improved the drug’s storage stability but also the drug’s resistance to the gastric acids of the stomach. The patents thus claimed the combination of a core containing both the drug and an alkaline compound, a water-soluble subcoating, and an enteric coating.

When Aktiebolaget sued Apotex for patent infringement, Apotex responded that the patents were invalid for obviousness over several references. One reference disclosed an omeprazole tablet that included an omeprazole core without an alkaline component, and an enteric coating but no subcoating. The other references disclosed various drugs that had both an enteric coating and a subcoating, but did not include omeprazole or any other drug that behaved in the same way in the stomach or intestine. Aktiebolaget responded that the first reference indicated neither the need to stabilize the omeprazole nor the undesirable reaction between the enteric coating and the omeprazole in the core.

The Aktiebolaget inventors had discovered that the instability of omeprazole when encased in an enteric coating was caused by the reaction between the omeprazole and the coating. Once this was understood, the use of a protective subcoating may have been an obvious solution, but the discovery of the cause of the problem made the invention nonobvious and the patents’ validity was upheld (8).

“But they said it couldn’t be done!”

Conventional wisdom (i.e., prior art) may suggest that a certain idea is not functional and thereby discourage those working in the area from adopting the idea. When an inventor then attempts the idea and demonstrates that it is indeed functional and produces a beneficial effect, the inventor often argues that the prior art “teaches away” from the idea, and that the inventor who discovers its benefits should be awarded a patent for the discovery. If the prior art disparages an invention while disclosing it in full (disclosing all of its elements in the same combination or arrangement), the question is one of novelty, and a teaching-away argument will not succeed because the prior art disclosure, despite its negativity, deprives the invention of novelty. However, when two or more prior art documents must be combined to achieve all elements of the invention, and one of the documents discourages its readers from incorporating or substituting an element from the other, the invention is novel and the question is one of nonobviousness. As a nonobviousness argument, the teaching-away argument may very well succeed.

Crocs, Inc., succeeded with such an argument with its Patent No. 6,993,858 (9). The patent claims ventilated shoes similar to flip-flops or sandals that include a strap made of foam. The foam provides friction between the strap and the base section of the shoe and, once the wearer adjusts the strap to a desired angle, the friction holds the strap at that angle,...

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