Enforceability of the ‘995 patent After analyzing legal principles of inequitable conduct, the Court concluded that Ranbaxy failed to established by clear and convincing evidence that the ‘995 patent was procured through inequitable conduct. In its arguments, Ranbaxy contended that Warner-Lambert withheld information concerning other patents in their portfolio and misrepresented the cholesterol inhibition activity of the compounds at issue. Specifically, Ranbaxy contended that the ‘080 patent and its CIP application were not disclosed to the PTO, and both these references give rise to prima facie unpatentability of the ‘995 patent based on obvious-type double patenting. The Court concluded that although the ‘080 patent was not revealed during the prosecution of the ‘995 patent, the Court is not persuaded that it was intentionally withheld. As for the data submission issue, the Court likewise concluded that it is not persuaded that the instances of non-disclosure cited by Ranbaxy are sufficient to demonstrate intent to deceive the PTO. District Court Judgment Judge Farnan Jr. is his memorandum opinion concluded: that (1) Ranbaxy’s ANDA product literally infringes the ‘893 and ‘995 patents; (2) that the ‘893 patent term extension is not invalid; and (3) that claim 6 is not invalid for failure to comply with section 112 paragraph 4; as anticipated or obvious; or for non-statutory double patenting; and (4) that the ‘995 patent is not unenforceable due to inequitable conduct. Battle II Round II: Ranbaxy Appealed to CAFC Following the District Court ruling, Ranbaxy filed an appeal with the U.S. Courts of Appeals for the Federal Circuit. CAFC, however, agreed with the District Court’s claim construction of claim 1 of the ‘893 patent and thus affirmed the District Court’s finding of infringement. And also affirmed the District Court’s ruling that the ‘893 patent term extension was not invalid. With regard to the ‘995 patent, CAFC reverse the District Court’s ruling regarding the question of invalidity of the ‘893 patent under section 112 paragraph 4. Citing one of its recent judgments in Curtiss-Wright Flow Control Corp., 438 F. 3d 1374, 1380 (Fed. Circ. 2006), CAFC suggested that a violation of section 112, paragraph 4 renders a patent invalid just as violations of other paragraphs of section 112 would. The CAFC concluded that Ranbaxy correctly argued that claim 6 fails to “specify a further limitation of the subject-matter” of the claim to which it refers because it is completely outside the scope of claim 2. Accordingly, CAFC reversed the district court ruling with respect to the question of invalidity under section 112, paragraph 4 and invalidated claim 6 of the ‘995 patent for failure to comply with section 112, paragraph 4.