Pfizer, Inc., et al. v. Ranbaxy Laboratories, Limited, et al.
Claim Was Invalidated for Failure to Comply with Section 112, Paragraph 4.
The CAFC affirmed the finding of infringement of Pfizer’s U.S. Pat. No. 4,681,893 (the ‘893 patent) but reversed the district court’s ruling with respect to U.S. Pat. No. 5,273,995 (the ‘995 patent) and found Claim 6 of the ‘995 patent invalid.
The technology of the ‘995 patent is related to atorvastatin calcium, commonly known as the cholesterol-lowering drug Lipitor. The relevant ‘995 claims can be simply stated as follows:
1. Atorvastatin acid; or a atorvastatin lactone; or pharmaceutically acceptable salts thereof.
2. A compound of claim 1 which is atorvastatin acid.
6. The hemicalcium salt of the compound of claim 2.
As the district court noted, Claim 2 does not include pharmaceutically acceptable salts of atorvastatin acid. Thus, Claim 6 did not properly incorporate subject matter by reference and specify a further limitation of Claim 2 as required by Section 112, paragraph 4, However, the district court refused to invalidate the claim, citing that the defect was a matter of form and not substance. In essence, the district court declined to find that the drafting problem was sufficient to render the claim invalid if read consistently with its meaning to those skilled in the art.
The CAFC recognized that Claim 6 could have been properly drafted as dependent from Claim 1. However, the CAFC also stated that courts “should not rewrite claims to preserve validity.” As Claim 6 failed to specify a further limitation of the subject matter of Claim 2, Claim 6 was held invalid for failure to comply with section 112, paragraph 4.
Applicants are required “to satisify certain requirements before obtaining a patent” and invalidating a claim for failure to comply with section 112, paragraph 4 “does not exalt form over substance.”
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Is it simply a matter of fixing the patent with the PTO and suing Ranbaxy again or is ‘995 gone for good?
I wouldn’t say that it is “simply” a matter of fixing the patent, but it certainly remains to be seen whether ‘995 is gone for good.
According to a Pfizer spokesperson quoted in the CNN article I cited, Pfizer will try to “correct some technicalities in the patent with the patent office and, if that doesn’t work, will seek a review in the Court of Appeals.”
I suspect that the correction that was mentioned means a reissue application. A reissue application generally may be filed to correct an error in the patent which was made without any deceptive intention, where, as a result of the error, the patent is deemed wholly or partly inoperative or invalid.
The most common bases for filing a reissue application are:
(A) the claims are too narrow or too broad;
(B) the disclosure contains inaccuracies;
(C) applicant failed to or incorrectly claimed foreign priority; and
(D) applicant failed to make reference to or incorrectly made reference to prior copending applications.
See MPEP 1402.
I agree with Dennis Crouch at Patently-O, who stated in his analysis of this opinion that “there is some question as to whether the defect here falls within an identified category.”
Thank you for the feedback and the link. I am not sure if Dennis’ example is quite right in comparing to this case. The patentee self inflicted over a reissue attempt to fix the first reissue process and not direct to the patent. The Appeals Court stated how to fix the issue. I suspect the approach will be a reissue under your category (A) with the original claim 6 being too broad (as in a dependent claim not further limiting the scope off of claim 2) and making it a dependent claim off of claim 1. That should satisfy the PTO and the courts and get back their injunction for the term of the ‘995 patent. I would say the odds favor Pfizer. Again, thanks for the back and forth, it has been insightful for me.
Thank you also for the perceptive comments. As for the back and forth . . . no problem, that’s why the blog is here!