Most people are aware that there is no such thing as a “patent police”. The duty of monitoring the marketplace for infringement of a patent falls on the shoulders of the patent holder. If this duty is not fulfilled, then the patent cannot be used to stop others from making, using or selling the relevant invention, because the identity of the “others” will not be known.

Monitoring the marketplace for infringement typically involves a non-trivial investigation effort on the part of the patent holder. The reason is that infringers rarely trumpet their infringing activities. What is not widely appreciated, however, is that the amount, complexity and cost of such investigation can vary significantly depending upon the nature of the invention that is claimed in a patent.

For example, consider two hypothetical patents owned by a company that manufactures screws. The first patent covers a new type of screw whose head has a triangular hole for receiving a triangular screwdriver bit. The second covers a new method of manufacturing screws that results in conventional slotted screws but only requires a fraction of the power historically needed to manufacture such screws. The company initially treats the patents as being equally important within its patent portfolio.

It would be straightforward to detect infringement of the first patent, as any manufacturer producing screws having heads with triangular holes is likely to be an infringer. Monitoring for infringement of this patent may therefore be as simple as periodically visiting local hardware stores and scanning the shelves for competing screws of the relevant type.

Detecting infringement of the second patent, on the other hand, may be more challenging. The reason is that the end product of the inventive manufacturing method – conventional slotted screws – may be indistinguishable from screws made by non-infringing manufacturing methods. To detect infringement of the second patent, the patent holder may need to examine competitors’ factories or assembly lines. Of course, a competitor is unlikely to provide access to its facilities, especially for the purpose of inviting a patent infringement lawsuit. The patent holder may therefore be forced to resort to alternative methods for detecting infringement, such as scouring competitors’ websites or technical documentation for admissions evidencing infringement (e.g. “We now manufacture our screws more efficiently using <the patented method>!”). This approach may fall flat, however, because savvy competitors may intentionally limit the amount of product information accessible by non-customers, precisely to avoid providing unknown patent holders with ammunition for a patent infringement lawsuit. Absent any information regarding competitors’ manufacturing methods, the company may be reluctant to allege infringement of its second patent. The patent may therefore be considered to have diminished strategic value within the company’s patent portfolio.

In some fields, there may be no getting around the practical difficulty of detecting patent infringement. For example, patents for computer-based inventions are often directed to the inner workings of computer hardware or software, which may not be readily apparent from the operation of an infringing device. Reverse-engineering competitors’ products may provide insight as to whether infringement is likely. Indeed, companies whose primary purpose is to reverse-engineer products
(e.g. Ottawa-based Chipworks) have arisen, likely in part to satisfy this need. The cost of reverse-engineering, which may be significant, might be justifiable as likely paling in comparison to the cost of doing nothing, in terms of potential lost revenues resulting from an infringing competitor product. At least in the case of software, however, many end user licences now expressly bar reverse-engineering. Perhaps as a consequence, the number of patent applications directed to the graphical user interface (“GUI”) of computer-based products has increased in recent years, with the rationale being that GUI features are more easily spotted in competing products.

The above-described potential hurdles to detecting patent infringement in certain fields should not be understood to suggest that no patents should be sought in these fields. On the contrary, because each patent holder presumably faces the same hurdles in detecting infringement by competitors, the playing field is effectively levelled as between competitors in each field. Moreover, it should be appreciated that ease of detecting infringement is but one factor to consider in one’s patent acquisition strategy. Other considerations, such the potential value of a patent in garnering investment, generating licensing revenue, or promoting strategic partnerships, may deserve equal or perhaps even greater weight. Nevertheless, it is valuable to consider ease of detecting infringement early in the patent acquisition process, to ensure that one’s patent procurement budget is wisely allocated. Had the above fictitious company followed this advice, it might have recognised the particular strategic value of its first patent early in its history.

Peter A. Elyjiw, Toronto