A Guide to Patent Law

Identifying Patentable Inventions

For an idea to be patentable, it must consist of statutory subject matter. United States patent law permits the granting of a patent on the following statutory subject matter:

• A process, such as a method of applying a vapor barrier for silicon materials.
• A machine, such as a new instrument to deposit uniform layers of metallic compounds.
• An article of manufacture, such as an assay kit for an infectious disease or class of diseases.
• A composition of matter, such as a new molecule (characterized by amino acid sequence or base-pairs) or a new chemical compound.
• New and useful improvements of the above.
• Any distinct and new variety of plant which is asexually reproduced.
• Any new, original, and ornamental design for an article of manufacture.

If an idea fits into one of the previous categories, United States patent law also requires that the invention be: 1. New or Novel: The invention must be demonstrably different from publicly available ideas, inventions, or products (so-called "prior art"). This does not mean that every aspect of an invention must be novel. For example, new uses of known processes, machines, compositions of matter and materials are patentable. Incremental improvements on known processes may also be patentable. 2. Useful: The invention must have some application or utility or be an improvement over existing products and/or techniques. 3. Non-Obvious: The invention cannot be obvious to a person of "ordinary skill" in the field; non-obviousness usually is demonstrated by showing that practicing the invention yields surprising, unexpected results.

Each of these three criteria is open to interpretation. Establishing novelty and/or usefulness often relies on arbitrary value judgments. For example, it may not be clear to the United States Patent and Trademark Office (USPTO) that a new gene-sequencing instrument is "demonstrably different" from other existing models, or that the use of a new hybridoma for narrow research purposes is sufficiently significant to be called a "useful" improvement over existing techniques.

Despite the possible variety of definitions of novelty and usefulness, the concept of "non-obviousness" is the most complex of these three patentability requirements. It is subject to broad and often inexact interpretation. For example, it might be argued that a new method of controlling protein production in bacteria is obvious in the face of prior art because it relies on a collection of well-known, existing and proven concepts. Conversely, one could argue the same method is not obvious because certain specific elements of the method yield surprising, unexpected results. Judging what is obvious to one of "ordinary skill" in an art is rarely straightforward, especially in technologically complex and rapidly changing fields.

The three criteria of novelty, usefulness and non-obviousness generally are the focal points of the USPTO's evaluation of patent applications. Obviousness is the reason most frequently cited by patent examiners as to why an invention is not patentable.

Finally, patent law states that inventions may be patented if they have been reduced to practice, even if a physical embodiment of the invention has not been realized ("constructive" reduction to practice, as described in the preceding section). Therefore, some extrapolation about an inventive concept can be included in a patent application.

The extent of permissible extrapolation, however, can be the subject of dispute with the USPTO. For example, an invention which claims a broad class of chemical compounds is rarely granted a patent, unless evidence is presented that several different representative members of the class have actually been made. A claim even to a single new compound usually must include a detailed description of its actual synthesis in order to receive patent protection. In the case of machines or mechanical devices, the requirements of the USPTO are much less strict.

Conception of Invention

For patent purposes, inventions are made in two stages:

1. "Conception," which is the intellectual act of creating a complete inventive concept, including ideas for making the invention and methods of using it.
2. "Reduction to practice" of the inventive concept. This is defined either as "constructive" reduction to practice (patent application), even though physical embodiment of the invention may not have been realized, or "actual" reduction to practice which involves making a physical embodiment of an invention (for example, a prototype), and using it successfully for its intended purpose.

For example, a scientist might claim to have invented a novel surgical instrument or a new environmental monitor and a patent application could be filed on the invention even though the device had never actually been built. In this example, the conception would be the intellectual concept of the instrument and its use for medical or environmental applications. The reduction to practice would be a constructive reduction to practice achieved by the filing of a patent application describing the instrument and its intended use. (If the invention had been built and used, actual reduction to practice would have been achieved.)

For chemical and bio-pharmaceutical products, however, it is usually not possible to obtain patent protection unless at least one example of the product has actually been made. If the invention claimed is broad enough to cover a class of products, it will be necessary to have made a representative number of the products of that class. In general, it has not been necessary to have proof of the product's usefulness if the claim of usefulness is plausible.

In order to obtain a patent, all inventors, through their patent attorneys, ultimately have to convince the U.S. Patent and Trademark Office (USPTO), and its foreign counterparts, that their invention meets the requirements of patent law.