Can you tell which of the following preambles limits the claim?
1. A method of treating or preventing macrocytic megaloblastic anemia in humans which anemia is caused by either folic acid deficiency or by vitamin B12 deficiency which comprises …
Jansen v. Rexall Sundown, Inc. (Fed. Cir. 2003).
1. A method for reducing hematologic toxicity in a cancer patient undergoing taxol treatment comprising ...
Bristol-Myers Squibb Co. v. Ben Venue Labs., Inc. (Fed. Cir. 2001).
If you guessed the Jansen claim, you guessed right. If you are helplessly confused you are not alone! Whether a preamble limits a claim can be one of the most confusing issues in patent law, and the Manual of Patent Examination and Procedures offers no help. According to MPEP 2111.02 (“Effect of Preamble”):
The determination of whether a preamble limits a claim is made on a case-by-case basis in light of the facts in each case; there is no litmus test defining when a preamble limits the scope of a claim. … A claim preamble has the import that the claim as a whole suggests for it.
So how can we determine whether a preamble will be given limiting effect in court or during prosecution? And perhaps most importantly for a prosecuting attorney, what can be done to ensure that the preamble is given a limiting effect?
The Federal Circuit typically asks questions such as:
- -- Does the body of the claim refer back to the preamble? For example, do the preamble and the body of the claim both describe to the same patient?
- -- Does another claim describe the same steps in the body of the claim, and differ only by the language in the preamble? If so, the doctrine of claim differentiation may apply.
- -- Did the applicant add language to the preamble to overcome a rejection by the Examiner? I.e., did the Examiner grant the patent based on the intended use?
The Federal Circuit cited these factors in Jansen v. Rexall Sundown, and more recently the Patent Trial and Appeals Board applied these factors in Apotex, Inc. et al. v. Novartis AG (PTAB June 11, 2018).
However, the most important issue I have identified, which I have not found written in a textbook, is whether the body of the claim defines a novel process. If the body of the claim is not novel, the preamble is not likely to limit the claim. Conversely, if the body of the claim is novel, the preamble is likely to limit the claim.
If, as the prosecuting attorney, you structure the prosecution so that questions 1-3 are answered in the affirmative, chances are, if the body of the claim is novel, the preamble will be given limiting effect, and you will have a much stronger claim.
Consider for example the full text of the above claims from Jansen v. Rexall Sundown and Bristol-Myers v. Ben Venue. The Jansen claim read:
1. A method of treating or preventing macrocytic megaloblastic anemia in humans which anemia is caused by either folic acid deficiency or by vitamin B12 deficiency which comprises administering a daily oral dosage of a vitamin preparation to a human in need thereof comprising at least about 0.5 mg. of vitamin B12 and at least about 0.5 mg. of folic acid.
The claim body defined a novel method, and the preamble was given a limiting effect. In contrast the Bristol-Myers claim read:
1. A method for reducing hematologic toxicity in a cancer patient undergoing taxol treatment comprising parenterally administering to said patient an antineoplastically effective amount of about 135-175 mg/m2 taxol over a period of about three hours.
The body of the claim did not define a novel method, and the preamble was not given a limiting effect.
This distinction makes perfect sense, and illustrates the importance of the old maxim, “that which infringes, if later, would anticipate, if earlier.” Peters v. Active Mfg. Co. (U.S. 1889) Otherwise, the doctor who had been parenterally administering “135-175 mg/m2 taxol over a period of about three hours” for years before Bristol Myers’ discovery could be halted from doing so simply because Bristol-Myers discovered a new benefit of this old therapy.
The same is not true when claiming a method which is allegedly obvious based on the prior art, which gives rise to two issues we will tackle in upcoming blogs:
- -- Is inherency applied differently in an obviousness rejection than a novelty rejection?
- -- When does a claim cross the line from obviousness to anticipation?
Hang tight! I can’t wait to see how these blogs turn out.