Interferences: rights of the first inventor in the US

What happens if someone else claims to have invented your invention? In the United States, only the first inventor has rights to patent protection of an invention. When two or more parties claim to have invented the same invention, an interference determines the actual first inventor, who will subsequently be awarded the patent rights.

The rights of the first inventor are unique to US patent law. Most other jurisdictions, including Europe, Canada and Japan, award the patent rights to the inventor who first files a patent application. The 'first to file' jurisdictions consider the diligence of the first filing inventor most deserving of patent protection, whereas US patent policy recognizes the individual's right to their creation. In all jurisdictions, the application must be filed on the behalf of an actual inventor, because a party who simply derives or steals an invention from someone else cannot obtain patent rights. These underlying policies shape the legal rules and procedures for interferences. Box 1

Triggering an interference

The examiner of a pending patent application has the discretion to declare an interference to determine who invented the claimed invention first — that is, the priority of invention — on his or her own initiative or at the suggestion of an applicant. An interference can be declared between two or more pending applications or an issued patent and one or more pending applications that claim the same (or substantially the same) invention. An examiner determines whether the same invention is claimed using the two-way patentability test. Simply stated, if invention A anticipates or renders obvious invention B, and vice versa, the examiner can declare an 'interference in fact'. Once the examiner determines that the same invention is claimed and can be patented by each party, the examiner defines the subject of the interference using one or more hypothetical claims or 'counts'.

Once triggered, interferences are procedurally complex, resembling a mini-trial with motions and discovery that culminates in a hearing before an administrative trial judge. The interference focuses on a factual determination of the priority of invention as well as some patentability issues.

Conception and reduction to practice

A party establishes priority of inventorship by showing that he or she first made the invention or first conceived of the invention and exercise reasonable diligence in later making it.

Conception of an invention lies in the mental construction of a complete and operative invention. The party must show possession of every invention feature and prove by corroborating evidence that the party disclosed the invention to others in such a way that someone else in the field could make and use it. Such evidence can include notebook entries and sufficiently detailed models that fully convey the invention. Corroboration of conception requires something more than the inventor's testimony. The strongest evidence is typically a complete and detailed description of the invention signed by a disinterested third party.

Reduction to practice looks to when an operative invention was actually made. The filing of a patent application itself can serve as a 'constructive' reduction to practice if certain patentability requirements are met. Alternatively, an inventor establishes reduction to practice by demonstrating the actual making of an operative embodiment of the invention. Definitive reduction to practice can be complicated for biotechnological inventions because of the testing associated with determining whether or when a biological invention is actually able to perform as claimed. For example, in some cancer therapy inventions, a patent application contains only in vitro and animal study data. Yet, a method of treating a patient requires clinical studies to demonstrate efficacy that usually occur years after the application is filed. In such cases, reduction to practice relies on the subjective strength of the preclinical data supporting the claimed invention.

In a nuance peculiar to biotechnological inventions, conception of certain inventions are not recognized in US patent law without a simultaneous reduction to practice. For example, conception of novel DNA sequences and new chemical compounds can necessitate the disclosure of a definitive structure, name or formula, or definitive chemical or physical properties — an effective reduction to practice — in order to prove conception.

Winning the interference

If an inventor demonstrates the earliest conception and reduction to practice, he or she will prevail in an interference. If, however, an inventor has the earliest date of conception but reduces the invention to practice after the second inventor, a more complicated analysis ensues. The inventor with the earliest conception date also must show a reasonable diligence — that is, consistent efforts — towards making the invention from the date of conception forward. If the inventor demonstrates such efforts, then the inventor with the earliest conception date prevails. However, if the first inventor abandons, suppresses or conceals the invention rather than exercising reasonable diligence in reducing it to practice, the second inventor can be granted priority and the associated patent rights.

Box 1: Strategic business considerations

The primary consideration in any patent decision should be whether your overall strategic and business goals benefit from investing resources into patenting efforts. This is particularly true of an interference, a proceeding that is usually expensive and time-consuming. So, here are a few questions to consider:

• Is there an easier way to obtain the necessary patent protection? Sometimes amending the claims to avoid the interference while retaining protection of the commercially valuable invention might be an option.

• What is the expected benefit from winning the interference? The cost of an interference in time and resources can significantly outweigh the expected benefit of winning. On the other hand, if a successful interference knocks out a dominating patent in a sector in which you will be selling your product, the time and money might be worth it.

• Can you afford a significant delay in obtaining patent protection? In extreme cases, the resolution of an interference can take up to 10 years. Markets for products rarely lay fallow for such long periods. You should therefore consider whether your invention is one that will still provide adequate return if the interference process lasts for several years.