Ex parte Cameron et al. (PTAB, July 5, 2017) (Appeal No. 2015-003506, in Application Serial No. 12/185,585) (before Prats, Schneider, and Majors, APJ) (opinion by Prats, APJ).

The Patent Trial and Appeal Board recently considered the scope of the transitional phrase “consisting essentially of” in Ex parte Cameron that published on July 5, 2017.

The ‘585 Application claimed an oral composition “consisting essentially of” morin; triclosan; a fluoride ion source; a water-humectant phase; and an ingredient of a solubilizing agent, a polishing agent, a surfactant, a flavoring agent, a sweetener, a synthetic anionic polycarboxylate, or a combination thereof (Appeal Brief, p. 14, claim 1). The Examiner rejected the claim as obvious over Waterfield (US 5,258,173) (Final Office Action of January 30, 2012). Waterfield discloses a composition that includes a stannous salt in addition to morin, tricolsan, a fluoride source, a humectant phase, and ingredients such as surfactants, flavoring agents, and sweeteners.

A major issue before the PTAB was whether the “consisting essentially of” language in claim 1 excluded the stannous ions described in Waterfield.

Appellants contended that Waterfield’s stannous ions were excluded by the “consisting essentially of” language because stannous ions were anti-bacterial compounds that would necessarily affect the claimed essential element, triclosan, which was an anti-bacterial element. What is interesting in this case is that, during prosecution, original claims 7 and 13, which recited using stannous fluoride as the fluoride ion source, were canceled. Appellants contended that the cancelation of claims 7 and 13 equated to a surrender of the claimed subject matter and further contended that the surrender of the claimed subject matter equated to a showing that the surrendered subject matter would affect the basic and novel properties of their invention.

In affirming the Examiner’s rejections, the PTAB emphasized that the term “consisting essentially of” specified that the invention necessarily included the listed ingredients and was open to unlisted ingredients that did not materially affect the basic and novel properties of the invention. The PTAB first noted that Appellants did not provide any persuasive evidence in either Waterfield or in the Specification suggesting that stannous ions would affect the anti-bacterial properties of triclosan. The PTAB then pointed out that Appellants did not identify teachings in the Specification explaining what the basic and novel properties of the claimed invention were such that the inclusion of stannous ions would be detrimental to (i.e., materially affect) such properties. Finally, the PTAB noted that there was no authority holding that “surrender of claimed subject matter [during prosecution before the PTO] equates to a showing that the surrendered subject matter would affect the basic and novel properties of the disclosed invention, to the extent that the surrendered subject matter would be excluded from claims including the ‘consisting essentially of’ transitional phrase.” Instead, the PTAB held that “[surrendered] or not, the language of the original claims in this appeal, at minimum, suggests the presence of stannous compounds/ions do not materially affect basic and novel characteristics of the invention.”

The Manual of Patent Examining Procedure (MPEP) provides that the “consisting essentially of” transitional language will be construed as equivalent to “comprising”, absent a clear indication in the specification or claims of what the basic and novel characteristics actually are (MPEP, § 2111.03). In addition, if an applicant contends that additional elements in the prior art are excluded by the “consisting essentially of” language, it is the applicant who has the burden of showing that the introduction of the additional elements would materially change the characteristics of applicant’s invention (MPEP, § 2111.03).

Appellants in Ex parte Cameron failed to identify what the basic and novel characteristics of their invention were and failed to satisfy their burden of showing the stannous ions described in Waterfield would materially affect the basic and novel characteristics of their invention.