Opinion ID: 809417
Heading Depth: 4
Heading Rank: 2

Heading: Appellants’ ANDA products infringe the

Text: “substantially all” limitation under the doctrine of equivalents Turning now to the district court’s analysis of infringement of the “substantially all” limitation, we review the district court’s findings of infringement under the doctrine of equivalents for clear error. Conoco, 460 F.3d at 1357. The district court stated that the multilayer tablet claimed in the ’183 patent requires “substantially all of the naproxen and triptan [to be] segregated and separated for the purpose of independent dissolution.” Pozen, 800 F. Supp. 2d at 810. The parties’ experts agreed that the function was to have “separate, distinct layers of sumatriptan and naproxen. The way in which this function is achieved is by formulating the sumatriptan and naproxen in different manners to create physical barriers. The result is that substantially naproxen is separated from the [sumatriptan], thereby providing independent dissolution.” Id. The district court found that Par’s ANDA product performs essentially the same function, by segregating the naproxen and sumatriptan into two layers. Id. This is achieved by formulating them differently, specifically, by 33 POZEN INC v. PAR PHARMA using a polymer binder to form 15% of the naproxen into granules which are added to the sumatriptan layer. Id. The result is that one layer has 100% of the sumatriptan with 15% of the naproxen, and another layer has the remaining 85% of the naproxen, substantially all separated and segregated into two layers. Id. Therefore, the district court determined, Par’s ANDA product performs the same function, in the same way, and achieves the same result, and satisfies all of the limitations of the ’183 patent under the doctrine of equivalents. The district court also found that DRL’s ANDA product performs the same function of achieving separate, distinct layers by segregating the triptan and naproxen. Id. This is achieved by granulating 15% of the sumatriptan with a polymer binder and then spraying it on the naproxen which has been granulated with a polymer binder as well; the remaining 85% of the sumatriptan forms the other layer. Id. “Thus, substantially all the triptan is segregated and separated into the equivalent of a first distinct layer, in an equivalent side-by-side arrangement, and this achieves the result of independent dissolution.” Id. at 811. Therefore, the district court determined, DRL’s ANDA product performs the same function, in the same way, and achieves the same result, and satisfies all of the limitations of the ’183 patent under the doctrine of equivalents. Appellants argue that their ANDA products do not achieve separate distinct layers because one of the layers has both agents. However, their products contain a bilayer tablet, with 100% of one agent in one layer, and 85% of the other agent in the other layer. We determine, as the district court did, that this structure is insubstantially different from a bilayer tablet with 90% of the total therapeutic agent present in the tablet included in a single layer. POZEN INC v. PAR PHARMA 34 Appellants contend that their products are admixtures which Pozen specifically disclaimed during the ’183 patent prosecution. DRL argues that the district court improperly limited Pozen’s disclaimer to admixtures that achieve independent dissolution, when it really disclaimed admixtures in general. We agree that Pozen did in fact disclaim admixtures when it stated before the PTO: The present claims require that naproxen and [sumatriptan] be in a tablet in which they are seg- regated from one another in a “side by side ar- rangement” and in which their dissolution occurs independently of one another. The claims are lim- ited to one very specific tablet architecture. Among the dosage forms falling outside the claims are: admixtures; any dosage forms other than tab- lets; tablets in which one drug is in a core and surrounded by a layer or coating containing the second drug; and tablets containing multiple drug release pellets or microparticles. J.A.240667. However, the Appellants’ ANDA products are not admixtures, i.e. substances with blended or mixed ingredients, because substantially all of the agents are separated and segregated into two distinct layers, as explained above. Based on the evidence above, the district court did not clearly err in finding that Par’s ANDA products and DRL’s ANDA products met the “substantially all” limitation of the ’183 patent under the doctrine of equivalents.