Blurred patent scope good for both patent owner and accused infringer
In Meadwestvaco v. Rexam (Fed. Cir., 2013), a perfume bottle manufacturer figured out how to hide a tube within a perfume liquid. The user doesn’t see an unattractive tube sticking down into the perfume liquid. The manufacturer achieved this by closely matching the refractive index of the perfume liquid and the plastic tube. The manufacturer obtained patent protection for the matched refractive index properties by claiming a plastic having a crystallinity not greater than 13%.
The invisible tube was an instant success and attracted many other competitors. When a patent issues, the claims define the scope of patent protection afforded under the patent. These claims are balanced with patentability and design arounds in mind. Anyone can get a narrow patent claim through the patent office. However, the real finesse is in overcoming a rejection by narrowing down a claim just enough to overcome the cited prior art but yet still be broad enough to prevent others from effectively entering the market.
In this case, the patent attorney or the client thought that not greater than 13% crystalinity was sufficiently broad. Competitors thought that they had figured out how to match the refractive index of the perfume liquid with plastic by blending the plastic so that the crystallinity is greater than 13%. As we’ve previously discussed, literal infringement is only found when each element of the claim is incorporated into the accused infringing device. If the accused infringing device fails to incorporate any one limitation, there is no literal infringement. Here, the accused infringing device lacked the “not greater than 13% crystallinity” limitation, and thus the accused infringer thought that they did not infringe the claim.
The case ultimately came down to a battle of the experts. To be expected, the patent owner’s expert based on his scientific tests showed that the accused infringing device had a crystallinity of less than 13%. The accused infringer’s expert testified that the accused infringing device had a crystallinity of greater than 13%. The court found the patent owner’s expert to be more credible than the accused infringer’s expert. Hence, infringement was found.
When you have claim language with a quantitative limitation that requires scientific testing, a battle of the experts will take place. What does this mean? Both sides will hire experts that are in line with their desired goals. As a result, the line of demarcation defining what does and what does not infringe is blurred. The claims are supposed to clearly delineate what is and is not infringing but it doesn’t. To me, this smells similar to the issues with patent trolls.
Hence, it is possible for the patent owner to go after more competitors by construing the claims to the outer bounds of the blurred claim scope. On the other hand, competitors would be more readily able to obtain an opinion of counsel of non infringement by construing the claims within the inner bounds of the blurred claim scope. At the end, litigation is more likely since both parties would most likely be unable to agree as to the proper scientific method to determine whether the accused infringing device is in or out of the scope of the claims.
On a side note, part of drafting a great patent application is to think of these types of design arounds. Patent attorneys need to push the envelope of the invention by finding out the bare minimal requirements for the invention to work. Asking smart questions to the inventor stretches the inventor’s imagination and also focuses the patent application on the point of the invention. Another way to anticipate these types of design arounds is to utilize bracketed ranges. For example, the specification can specify ranges of not greater than 20% but preferably not greater than 13%. In this way, the claims can first attempt the larger range then fall back to the narrower 13% range if the broader range is not allowable.
I invite you to contact me with your patent questions at (949) 433-0900 or [email protected]. Please feel free to forward this article to your friends. As an Orange County Patent Lawyer, I serve Orange County, Irvine, Los Angeles, San Diego and surrounding cities.