The US Court of Appeals for the Federal Circuit affirmed in part and vacated in part a Patent Trial & Appeal Board finding that the claims at issue were either invalid under 35 U.S.C. §112 as unsupported by written description or obvious under 35 U.S.C. §103. RAI Strategic Holdings, Inc. v. Philip Morris Products S.A., Case No. 22-1862 (Fed. Cir. Feb. 9, 2024) (Chen, Stoll, Cunningham, JJ.)

RAI owns a patent with claims directed to “electrically powered smoking devices that provide an inhalable vapor by heating tobacco or other substances without significant combustion.” Philip Morris challenged the patent in a post-grant review (PGR).

The Board issued a final written decision concluding that two dependent claims, which recited limitations requiring a heating member with “a length of about 75% to about 85% of a length of the disposable aerosol forming substance,” lacked § 112 written description support. The specification disclosed ranges of 75% – 125%, 80% – 120%, 85% – 115% and 90% – 110%. The Board explained that written description support was lacking because “the claimed range is different from and substantially narrower than the specific ranges disclosed in the specification.”

The Board found that the remaining claims were unpatentable as obvious based on a combination of prior art references where the heater found in one reference, Robinson, was replaced with the heater from another, Greim. Robinson explained that its heating element could be altered and acknowledged design choices, thus inviting skilled artisans to select an alternate appropriate heating element. Greim disclosed certain advantages to its heater. Thus, the Board found that a skilled artisan would have been motivated to replace Robinson’s heater with that of Greim, rendering the claims obvious. RAI appealed.

Citing its expert, RAI argued that the ranges disclosed in the specification all centered around 100%, so that a person of ordinary skill in the art (POSITA) would not “conclude that the inventors possessed a range that went no higher than 85%[.]” The Federal Circuit began by summarizing a line of numerical range cases, including:

• In re Wertheim (CCPA 1976), which found that a described range of 25% – 60%, with examples of 36% and 50%, supported a claim directed to a range of 35% – 60%.
• In re Blaser (CCPA 1977), which found that a described range of 60° – 200° C supported a claim reciting a range of 80° – 200° C.
• Kolmes v. World Fibers Corp. (Fed. Cir. 1997), which found that a described range of 4 – 12 turns per inch, and preference for 8 turns per inch, supported claims directed to 8 – 12 turns per inch.
• In re Baird (CCPA 1965), which found that a relatively unexplained disclosure of 32 – 176° F did not support claims directed to a range from 40° to “at least as low as” 60° F.
• Indivior UK v. Dr. Reddy’s Laboratories (Fed. Cir. 2021), which found that:
  • Disclosure of ranges of at least 25%, at least 50% and “any” value did not support claims directed to 40% – 60%.
  • The specification did support claims directed to “about 48.2%,” because that value was calculable by the POSITA from disclosed data points.

Against this backdrop, the Federal Circuit repeated Wertheim’s test assessing whether “the invention appellants seek to protect by their claims is part of the invention that appellants have described as theirs in the specification” – in other words, whether the disclosed and claimed inventions are different. The Court explained that “[a]mong other things, we consider whether ‘the broad described range pertains to a different invention than the narrower (and subsumed claimed range,’ in which case the specification does not provide written description support for the narrower claimed range.” Here, the Court found that the inventions were not different, noting that the specification need not expressly recite the claimed range for support and finding “no evidence suggesting that the broad described ranges . . . disclose a different invention than the claimed range of ‘about 75% to about 85%.’” Thus, the Court vacated and remanded for further proceedings consistent with its opinion.

As to the obviousness finding, RAI argued that Robinson’s invitation to experiment and make design choices only referred to alternate designs within Robinson itself. Referring to the substantial evidence standard of review, the Federal Circuit affirmed the Board’s determination, finding that it was reasonable for the Board to find that a POSITA would have been motivated by Robinson’s invitation to look at other heating elements, and that Greim and expert testimony further supported the Board’s determination.

Practice Note: Unlike the previous line of cases, RAI found description for a claimed range using two lower range endpoints in the specification. Thus, support for the endpoint as consistent with the same “invention” may be more important than the disclosed range’s similarity to the claimed range. To assess § 112 support, counsel should remember the key principles described by RAI and the line of cases it describes:

• Numerical range cases are highly fact specific.
• The level of predictability in the art is critical; predictable arts may allow greater differences between the specification and claims.
• Express recitation of the claimed range or endpoints in the specification is not required (but it helps).
• Assess whether the POSITA would understand the claimed and described inventions to be different or the same.