Sloppy Claim Drafting Invalidates Teva Copaxone Claims


08.27.13 Posted in Federal Circuit Opinions by

Teva Pharms. USA, Inc. v. Sandoz, Inc.,, No. 2012-1567 (Fed. Cir. 7/26/2013) (no reporter cite) (Rader, Moore, and Benson (sitting by designation from the District of Utah). Opinion by Moore.

Teva sued Mylan and Sandoz for patent infringement of nine patents covering copolymer-1, marketed by Teva as “Copaxone®” for the treatment of multiple sclerosis. Copolymer-1 is a polymer of alanine, glutamic acid, lysine, and tyrosine in a 6:2:5:1 ratio with a molecular weight of 5–9 kD.

The court first looked at definiteness under 35 USC § 112(b). For this analysis, the court divided the claims into two groups. Group I claims were directed to copolymer-1 having a molecular weight of 5-9 kD, made by a process of reacting and purifying. On claim construction, the molecular weight was determined to be an average molecular weight. Three different measures of average MW’s are discussed, Mp (peak mol. wt), Mn (number average mol. wt), and Mw (weight average mol. wt). The patent challengers argued that Teva inconsistently defined MW as Mw and Mp during prosecution, reinforcing ambiguity. The panel agreed. “It is undisputed that Group I claims contain an ambiguity because their plain language does not indicate which average molecular weight measure is intended.” Slip op. at 8. Significantly, the panel noted inconsistent statements during prosecution over which average molecular weight measure should be used.

Also, the panel noted drafting failings in Fig. 1, in which the peaks of the curves do not correspond to the values denoted as “average molecular weight” in the figure’s legend. The peak (Mp) of the 7.7 curve is clearly less than 7.7 kD on the x-axis, and the peak of the 12.0 curve is clearly less than 12 kD on the x-axis. The opinion states that it is therefore difficult to conclude that Mp is the intended measure for the Group I claims. The Group I claims are therefore indefinite.
By contrast, Group II claims, which recite copolymer I having over 75% of its mole fraction within a MW range of 2–20 kD, are held to be definite. The court states that the Group II claims do not recite the molecular weight in terms of a statistical measure (average molecular weights), but rather as precise points on the “molecular weight” axis. Thus, the scope of the Group II claims are readily ascertainable and not invalid for indefiniteness.

The opinion also reviewed the parties’ arguments on enablement (35 USC § 112(b)), which came down to a battle of experts, and concluded that the district court did not err in concluding that the claims were enabled. The panel also concluded that the claims were not obvious, based both on the prior art and secondary considerations. The prior art expressed a preference for a higher molecular weight product and taught away from the claimed invention. Regarding secondary considerations, the panel found that Copaxone® is coextensive with the asserted claims that trigger an assumption of a nexus between the drug’s commercial success and the claimed invention.

The panel also looked at infringement. The district court construed the claimed amino acid ratios of copolymer-1 to be “approximately 6:2:5:1.” The district court converted this to percentages of 42.9%, 14.3%, 35.7%, and 7.1% (without explaining the methodology). The panel did not tamper with this calculation. Each accused product was found to vary, on a percentage basis, by 4.5%, which met the “approximately 6:2:5:1” limitation. The claims were therefore literally infringed by the accused products.

Holdings: the Group II claims were therefore valid and infringed. The panel remanded the Group I claims because of the finding of invalidity.

This case is a good illustration of the danger of sloppy drafting. I have heard patent attorneys in the past argue in favor of ambiguous and obfuscatory drafting to maximize claim scope.  Here, the drafting attorneys and client may have felt no need to specify which average molecular weight measure in the specification, in the belief that this detail might be limiting. But in a case like this that comes down to a knock-down litigation,  when the courts start doing the claim construction to resolve ambiguous terms, the applicant loses control of the process and it becomes very expensive. In addition, the flaws in Fig. 1 undoubtedly annoyed the courts involved and was specifically cited in support of the Fed. Cir. conclusion that certain claims were indefinite.

These problems are all correctable by careful drafting by patent attorneys who understand the technology (and take the time to figure it out). And, they are preventable during prosecution also by patent attorneys who take the trouble to understand the underlying technology.



Comments are closed.

Stay In Touch!
Subscribe to our Newsletter!

Enter your email address to subscribe to this blog and receive notifications of new posts by email.

Search