Rounding the Bend: Declare Development and the Position of Extrinsic Proof

by Dennis Crouch

Actelion Prescribed drugs Ltd v. Mylan Prescribed drugs Inc., No. 2022-1889 (Fed. Cir. Nov. 6, 2023) [decision]

The Federal Circuit’s bread-and-butter over time has been declare constructions that always shock or confuse district courtroom judges. A part of the problem right here is that the majority Federal Circuit judges have construed 1000’s of patents and are deeply immersed within the regulation of declare building — whereas most district courtroom judges see declare building as a small a part of a patent case, which itself is a small a part of their total docket. The opposite a part of the problem, after all, is that no deference is given to the district courtroom’s declare building on enchantment. The following enchantment then recurrently seems like that regulation faculty class the place college students appeared to offer actually good solutions within the Socratic recreation, however the professor may by no means resist tweaking — “virtually proper.”

The Actelion case entails a standard scenario the place the patent claims embody a measurement however don’t state the extent of precision, and the courtroom is compelled to determine whether or not values barely outdoors the claimed vary is perhaps lined.

Actelion’s U.S. Patent Nos. 8,318,802 and eight,598,227 are directed to a brand new formulation of epoprostenol, a substance that naturally happens within the human physique and that’s helpful for treating cardiovascular ailments.  The claims seem directed to a product-by-process — a freeze dried powder (lyophilisate) fashioned from an answer that incorporates epoprostenol and that “has a pH of 13 or increased.” Mylan’s ANDA proposes a generic model that might have a pH constituted of an answer with pH slightly below 13.

The query for declare building is whether or not the requirement of “13 or increased” pH encompasses one thing akin to a pH 12.6.  For summary mathematicians, it’s fairly clear that 12.6 is lower than 13 — the other of what’s claimed. However, experimental scientists perceive {that a} measurement of 12.6 would possibly usually be correctly rounded to 13. The district courtroom adopted Actelion’s proposed building that “a pH of 13” consists of values that spherical to 13, comparable to 12.5 and concluded that Mylan’s method was infringing.  Mylan argued on enchantment that the time period requires an pH of “precisely” 13 — not values which are about or roughly 13.

The Federal Circuit opinion walked by way of varied components to assist it perceive the right building. Because the courtroom has held, the evaluation begins with the declare language, as it’s of main significance. Moreover, “the specification is all the time extremely related to the declare building evaluation” and is  usually “the only greatest information to the which means of a disputed time period.” Phillips v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005).

Declare Language: The courtroom examined whether or not the language setting a decrease restrict of “13” precludes rounding or not. The declare is written as an entire quantity, reasonably than in decimal type. The district courtroom famous that this concerned “two important figures’ with out implying any increased stage of precision.”  At oral arguments, the patentee’s counsel defined:

[The inventor] didn’t say 13.0, which is a determine that might have 10 instances the higher precision, and positively didn’t say ‘precisely 13’, which isn’t scientifically potential within the context of pH, since you’re speaking about measurement of billions of ions in a liter of water of hydrogen ions and figuring out their focus.

Oral args at 18:00. On the opposite aspect, in locations the specification appeared to equate 13.0 to the entire quantity 13.

Lack of Approximation Phrases: The courtroom famous that the declare lacks phrases like “about” that might suggest approximation and which are usually included inside patent claims. Because the courtroom defined, “In contrast to different declare phrases, the disputed declare time period lacks approximation language like ‘about.’”

Nature of pH Measurements: The courtroom thought-about whether or not pH values may be measured exactly or inherently require some margin of error. The courtroom famous Actelion’s argument that “it isn’t virtually potential to measure actual pH values” as a result of it could require counting each hydrogen ion in answer.

Specification: The specification alternately makes use of approximation phrases like “about” or lacks decimal factors when describing pH values. For instance, the specification states the pH is “ideally adjusted to about 12.5-13.5, most ideally 13.” This exhibits the inventor knew find out how to use “about” to suggest approximation, however didn’t for the “13” worth.  The assertion additionally means that 12.5 is totally different from 13.  Because the courtroom summarized, “the specification is inconsistent, additionally describing pH values like ‘13.0’, ‘11.58’, and ’13’ with out clear precision.”

Prosecution Historical past: Throughout patent prosecution, the patentee had distinguished its invention from a formulation with pH 12 — arguing that pH 13 exhibited considerably extra stability. However the prosecution historical past didn’t evaluate pH 13 with values in between 12 and 13. Because the courtroom defined, the examiner “drew a distinction between the steadiness of a composition with a pH of 13 and that of 12” however this didn’t handle whether or not pH 13 consists of values rounding to 13.

With declare building, the Federal Circuit has dominated that courts can very often construe claims based mostly solely upon intrinsic proof. However, at instances courts are permitted to go additional and entry extrinsic proof like scientific texts.  Right here, the Federal Circuit concluded that this can be a case the place extrinsic proof  is critical to grasp how a talented artisan would view the declare language when it comes to pH precision and important figures.  Because the courtroom defined, “this case is one the place the right declare building can’t be reached with out the help of extrinsic proof.” The appellate panel thus vacated the declare building and infringement judgment and remanded for the district courtroom to think about the extrinsic proof like scientific textbooks and maybe professional testimony within the strategy of reconsidering the declare building.

The panel consisted of Circuit Judges Reyna, Stoll, and Stark. Circuit Decide Stoll authored the opinion.

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This case highlights a problem that has led to say building disputes in quite a few circumstances involving measurements and precision with billions of {dollars} turning on so-called rounding errors. The dearth of readability stems from candidates not specifying the precision or margin of error for declare phrases both within the unique software or throughout prosecution. This ambiguity might be averted if the USPTO have been to place the onus on patent candidates to determine the precision and error margin for any measurements recited within the claims. For instance, the USPTO examiner may reject the claims as ambiguous based mostly upon the broadest cheap interpretation and require the applicant to make clear whether or not “a pH of 13” permits for values that spherical to 13 and if that’s the case, the appropriate variance (e.g. ± 0.1, ± 0.01 pH items).

Requiring patent candidates to explicitly determine the precision and error margin for measurements throughout prosecution would stop the necessity for courts to resort to extrinsic proof to resolve ambiguity that ought to have been addressed earlier than issuance. This may improve certainty round declare scope and cut back pointless litigation.

What do you suppose, ought to the USPTO contemplate extra methods to have candidates make clear declare time period precision when submitting and prosecuting purposes involving numerical measurements?