they did not teach the use of any pyrophosphate. Nor did they mention low temperature stability or flocculation. As Catherine Gray, one of the inventors of Advanced Formula PLAX(R), testified, the new formula was "completely different from the old formula." (Tr. at 344).
(ii) The Colgate Rinse
The Colgate mouth rinse (DX 1356) apparently was not before the Examiner. The Colgate product was sold for a brief period in 1987. Although it did make use of tetrasodium pyrophosphate, it did not include sodium lauryl sulfate or anything that would serve as a substitute therefor. (Tr. at 1695-96). There is nothing in the record concerning this product's capacity to remain free from cold temperature precipitation or flocculation.
(iii) The Procter & Gamble Prebrushing Rinse
The Procter & Gamble Prebrushing Rinse was covered by the Parran Patent, which was before the Examiner. (PX 1). The Procter & Gamble product was marketed briefly in 1989 as "Crest BrushMate" or as "Crest LiquaFloss" or as "BrushMate." The Parran Patent did involve the use of pyrophosphate salts, but in the context of providing an "anticalculus benefit," as opposed to an anti-plaque benefit. The Parran Patent called for a composition with a pH of from about 6.0 to about 10.0. There is no discussion in the Parran Patent of low temperature stability problems or low temperature precipitation or flocculation.
(iv) The Nabi Patent
Although the Nabi Patent was not listed in the '538 Patent, Rose also was the Examiner for the Nabi Patent. Moreover, the Nabi Patent was classified in multiple classes searched during examination of the '538 Patent, and reference was made to the Nabi Patent in the materials before Examiner Rose when he examined the '538 Patent. (PX 311). Hence, he is presumed to have had the Nabi Patent in mind when he considered the '538 Patent. See Polaroid Corp. v. Eastman Kodak Co., 641 F. Supp. 828, 833 (D. Mass. 1986) ("Prior art described in the specifications is expected to be considered by the Examiner . . . . Patent examiners are also presumed to be aware of patents which issued from applications they had earlier examined."), aff'd, 789 F.2d 1556 (Fed. Cir. 1986). Moreover, I find, as a factual matter, that Examiner Rose, an experienced examiner who was assigned many patent applications for oral health care products, had access to the Nabi Patent. (Tr. at 1875-92).
The Nabi Patent covered an antibacterial, antiplaque oral composition that could be substantially liquid in character, such as a mouthwash, or substantially pasty in character, such as a toothpaste. The oral composition used tricolosan as an antibacterial antiplaque agent. In liquid form it has a pH "generally in the range of about 4.5 to about 9 or 10 and most preferably about 6.5 to 7.5." (Nabi Patent, col. 7, lines 13-15). There is no disclosure in the Nabi Patent of any cold temperature impediment to stability or the problem of low temperature precipitation or flocculation.
(v) The Gaffar Patent
Rose also examined the Gaffar Patent, which was classified in multiple classes searched during examination of the '538 Patent, and reference was made to the Gaffar Patent in the materials before Rose when he examined the '538 Patent. (DX 1047). Hence, he is presumed to have had the Gaffar Patent in mind at the time he considered the '538 Patent. Moreover, I find, as a factual matter, that Examiner Rose had access to the Nabi Patent. (Tr. at 1875-92).
The Gaffar Patent covered an antibacterial, antiplaque, anticalculus oral composition such as a "dentrifice, mouthwash, lozenge or chewing gum." It teaches that the oral composition should be "free from or substantially free from tetrasodium pyrophosphate or a combination of tetrapotassium pyrophosphate and tetrasodium pyrophosphate." (Gaffar Patent, col. 3, lines 45-48).
(vi) The Van Wazer Publication
The Van Wazer publication (DX 1063) apparently was not before the Examiner. The portion of the Van Wazer book cited by Perrigo, however, does not relate to any kind of dental rinse or oral health care product; rather, it merely describes the utility of tetrasodium pyrophosphate in detergent and soap products used for industrial and household cleaning.
(b) The Level of Ordinary Skill in the Art
As the parties apparently agree, in this case a person having ordinary skill in the art would have an undergraduate degree in chemistry or biology with several years of experience.
(c) The Differences Between the Claimed Subject Matter and the Prior Art
There are substantial differences between the prior art and the claimed invention. None of the prior art references disclosed a pre-brushing dental rinse that included both sodium lauryl sulfate and tetrasodium pyrophosphate. None of the prior references addressed the problem of low temperature instability or low temperature precipitation or flocculation and thus none of the prior references proposed a solution for such a problem. In contrast, these are matters specifically addressed by the '538 Patent. Claim 1 of the '538 Patent teaches:
A stable, liquid oral prebrushing composition for loosening and removing plaque present on dental surfaces which composition is free from flocculation or crystal formation after storing for seven days at about 35 [degrees] F. or redissolves any flocculation or crystal formation at about 35 [degrees] F. on increasing the temperature of the composition to room temperature comprising a detergent builder selected from the group consisting of a dialkali metal pyrophosphate salt, a tetraalkali metal pyrophosphate salt and a mixture thereof providing at least about 0.3% by weight PO, and about 0.08 to about 2.0% by weight of sodium lauryl sulfate based on the weight of the prebrushing composition having a pH of about 7.2 to about 7.9.
Key features thus included stability, after storing for seven days at about 35 F., as well as the use of a combination of tetrasodium pyrophosphate and sodium lauryl sulfate, with a relatively narrow pH range of 7.2 to 7.9. None of the prior art references disclosed these features in this combination. Nor do I accept Perrigo's contention that it would have been obvious, at the time the invention was made, to substitute a pyrophosphate detergent builder such as tetrasodium pyrophosphate for the sodium borate-sodium bicarbonate builder combination used in the original formula PLAX(R) or to substitute sodium lauryl sulfate as a surfactant for the surfactants used in the Colgate rinse and the Procter & Gamble prebrushing rinse.
(d) Objective Evidence of Nonobviousness
Consideration of secondary or objective indicia of nonobviousness also leads to the conclusion that Perrigo has not met its burden of proving invalidity of the '538 Patent. Most significantly, Perrigo copied Advanced Formula PLAX(R) from Pfizer. That Perrigo resorted to copying the patented formula is strong evidence that the improvements introduced by Advanced Formula PLAX(R) were not obvious from the prior art references. Had they been obvious, Perrigo presumably would not have needed to resort to copying. See, e.g., Heidelberger, 21 F.3d at 1072.
Advanced Formula PLAX(R) was also a commercial success, as it achieved hundreds of millions of dollars in sales. This financial success strongly suggests that Pfizer had created a new product. See Demaco Corp. v. F. Von Langsdorff Licensing, Ltd., 851 F.2d 1387, 1391 (Fed. Cir.), cert. denied, 488 U.S. 956, 102 L. Ed. 2d 383, 109 S. Ct. 395 (1988).
Finally, other companies had tried but failed to develop a comparable product. Both Colgate and Procter & Gamble, two of the world's largest health care products companies, recognized the existence of a market for prebrushing dental rinses. Although both companies tried, neither was able to develop a successful product. If the improvements to Advanced Formula PLAX(R) were so obvious, one would have expected Colgate or Procter & Gamble to have had more success. See Symbol Techs. Inc. v. Opticon, Inc., 935 F.2d 1569, 1578-79 (Fed. Cir. 1991).
These factors, taken as a whole, demonstrate that a person skilled in the art would not have viewed Pfizer's invention as obvious at the time it was made. Therefore, Perrigo has failed to overcome the presumption of validity on the grounds of obviousness.
Hence, the first four grounds asserted for invalidity are rejected.
2. Section 112
Perrigo's fifth and sixth grounds for invalidity are based on 35 U.S.C. § 112, which sets forth certain specificity requirements for patent applications. The fifth argument relies on the second paragraph of section 112, which covers indefiniteness, and the sixth argument relies on the first paragraph of section 112, which covers enablement.
The second paragraph of section 112 provides:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as the invention.