In In re Glatt Air Techniques, Inc., the Federal Circuit reversed a decision of the U.S. Board of Patent Appeals and Interferences that held a claim obvious. The decision is remarkable in that it overturned the Board under the deferential “substantial evidence” standard, and found that the USPTO had not even established a prima facie case of obviousness. The court also criticized the Board for dismissing the applicant’s evidence of commercial success because it only related to one embodiment of the claims.

Glatt’s Invention

The claim at issue originally was granted as claim 5 of U.S. 5,236,503. That patent underwent ex parte reexamination, which led to the obviousness rejection.

The invention relates to fluidized bed coaters for applying a coating to particles, such as pharmaceutical ingredients. In so-called Wurster coaters, the particles are introduced into a chamber where they circulate in the path of the coating material which is sprayed from nozzle. Figure 1 of the ‘503 patent is reproduced below.

The invention addressed the problem of particle agglomeration that “occurs because the circulating particles prematurely enter the stream of coating spray before the spray pattern has fully developed.” The invention solves this problem by “shielding the coating spray nozzle to prevent the particles from entering the spray prematurely.”

Claim 5 recites the invention in “Jepson” format, with the preamble defining the prior art:

5. In a fluidized bed coater having a product container opening upwardly into an expansion chamber and downwardly into a lower plenum chamber through an air distribution plate/screen having openings formed therethrough for upward air flow from said lower plenum chamber into said product container, said product container including a substantially cylindrical partition spaced above said air distribution plate/screen for defining an inner upbed area and an outer downbed area, and an upwardly discharging spray nozzle mounted substantially centrally within said cylindrical partition, the improvement comprising shielding means positioned adjacent said spray nozzle for shielding the initial spray pattern developed by said nozzle against the entrance of particles moving upwardly through the upbed.

The claim uses “means-plus-function” language to recite the novel aspect of the invention. Thus, in accordance with 35 USC § 112, ¶6, this claim element is construed with reference to the specification of the ‘503 patent, which teaches that a “cylindrical partition” or “air wall or stream” can perform the shielding function.

The Obviousness Rejection

During the reexamination proceeding, claim 5 was rejected as being obvious in view of the prior art recited in the preamble of the claim (the non-bolded portion above) and German Patent DE 3323418 (Naunapper). An English translation of Naunapper was made of record during the reexamination proceeding.

Naunapper describes fluidized bed coaters with sensors that monitor gas flow to detect particle agglomeration. Naunapper teaches that agglomerates can be removed by “blowing through” with increased air flow.

The examiner asserted that Naunapper’s air flow read on the “shielding means” of claim 5.

The Federal Circuit summarized the Board’s grounds for affirmance:

[The Board] found that Naunapper “plainly teaches an arrangement that can provide . . . an air wall or stream surrounding the [coating spray] nozzle to address the same or similar problem discussed in the ’503 Patent,” and concluded that the arrangement described in Naunapper “would inherently or necessarily be capable of performing the same function recited for the claimed ‘shielding means.’”

The Substantial Evidence Standard

The Federal Circuit reviews the Board’s factual findings—such as its interpretation of a prior art reference—under the “substantial evidence” standard. This is a rather deferential standard that requires the court to consider the evidence on both sides and uphold the finding “if a reasonable mind might accept the evidence as adequate to support the Board’s factual conclusions.”

The Non-Obvious Difference Between Prevention and Cure

The Federal Circuit agreed with the Board’s finding that “Naunapper teaches modulating gas flow in the coating apparatus to control particle agglomeration,” but noted that “[i]t is readily apparent . . . that this technique does not shield circulating particles from entering the initial spray pattern.”

The court recognized a distinction between Naunapper’s “way to remedy the blockage caused by particle agglomeration using bursts of air” and Glatt’s invention, which “prevents the agglomeration from occurring in the first place. The court found:

Naunapper’s air source can be used to (1) circulate particles and (2) clear blockages. The air source cannot perform both of these functions simultaneously, and more importantly, neither of these functions constitutes shielding.

The Federal Circuit therefore determined that the Board’s factual finding that Naunapper taught a “shielding means” was “not supported by substantial evidence.” As such, the USPTO had “failed to make a proper prima facie case of obviousness.”

The Evidence of Commercial Success

During the reexamination proceeding and Board appeal, the applicant cited evidence of commercial success to rebut the asserted obviousness rejection. The evidence pertained to the applicant’s commercial embodiment, which used a physical shield for the “shielding means.”

Both the examiner and the Board rejected the evidence as being “not commensurate with in scope with claim 5,” because the claim also encompassed embodiments where the shielding means was an air wall.  The Federal Circuit rejected the USPTO’s position:

To the extent the PTO asserts that Glatt needed to submit commercial success evidence from multiple embodiments for that evidence to be commensurate in scope with claim 5, this position is not consistent with our precedent.

The court reasoned:

It seems unlikely that a company would sell a product containing multiple, redundant embodiments of a patented invention. The fact that Glatt’s commercial products only contain one type of shielding means does not make its commercial success evidence irrelevant.

Citing earlier Federal Circuit precedent, the court explained:

Commercial success evidence should be considered “so long as what was sold was within the scope of the claims.”

Could This Appeal Have Been Prevented?

I imagine that Glatt is satisfied with this decision, but I’m sure that it would rather not have had to pursue its appeal all the way to the Federal Circuit. When the court finds that it is “readily apparent” that the prior art does not teach what the USPTO says it taught, what more can or should the applicant have done during prosecution? Here, Glatt even submitted declaration evidence explaining Naunapper and the contribution of the invention, but the USPTO was not convinced.

The USPTO is developing and implementing new ways to measure and improve patent quality. Still, as long as rejections like this can make it past experienced examiners and the Board, it is applicants who bear the ultimate burden and expense of ensuring that patents that should be granted are granted.