Drafting a patent specification that accounts for issues across multiple jurisdictions is a lofty goal that many applicants pursue. Aiming for a compromise approach that tries to achieve a common application for varied jurisdictions can be challenging and so there may always be some specialization that occurs for specific jurisdictions, technologies, etc.
Sometimes the approach to an application is to focus on streamlining prosecution, reducing formalities, or minimizing fees. Other factors that are considered can be directed to critical aspects that, if not addressed, can lead to a total loss of all potential for patent rights in certain jurisdictions.
Today we address the latter. Some might argue that the topic below is the single greatest and most important advice for applications entering the US where the priority foreign application recites “means.”
Consider the example of a non-US priority application entering the US. Non-US drafters often recite means for performing a function, as the scope is considered broad - any means for performing the claimed function. This is more or less the approach that seems to be taken in Europe and Japan (EP and JP attorneys - please comment if you disagree!). See here, pages 3-4, for example. The US takes a more restrictive scope approach following 35 U.S.C. §112(f), which considers the scope as the corresponding structure in the specification and equivalents thereof. Much has been written on the difference in scope, but that is not the issue addressed here. Rather, the issue here is a much more deadly one. Because the US approach requires the scope to based on the structure in the specification (and equivalents thereof), the lack of disclosure of sufficient structure in the specification causes the means claim to lack written description and thus be invalid. Full stop.
Why would a patent application drafted by a competent non-US attorney ever have an important element of an invention described only as a means? Because, as noted above, this is a broad way to claim an element, especially when the element is a well-known element. As the invention may be directed to a combination of such a well-known element and other features, there is no need to describe well-known elements because everyone understands what is going on - everyone outside the US that is. In the US, this is a “gotcha”, as Citizen learned on appeal at the PTAB in 15/512,989.
Claim 1 of Citizen’s application is set forth below.
1. A machine tool comprising:
a workpiece holding unit to hold a workpiece;
a tool rest to hold a cutting tool for cutting the workpiece;
a feeding unit to feed the cutting tool toward the workpiece in a predetermined feeding direction via relative movement between the workpiece holding unit and the tool rest;
a vibration unit to relatively vibrate the workpiece holding unit and the tool rest so that the cutting tool is fed in the feeding direction while reciprocally vibrating in the feeding direction; and
a rotating unit to relatively rotate the workpiece and the cutting tool, the machine tool being capable of cutting the workpiece via the relative rotation between the workpiece and the cutting tool and via the feeding of the cutting tool toward the workpiece with the reciprocal vibration in the feeding direction, wherein the machine tool comprises an amplitude control unit to control an amplitude of the reciprocal vibration by the vibration unit, and the amplitude control unit is configured to reduce the amplitude of the reciprocal vibration by the vibration unit while the cutting tool is fed in the feeding direction when the cutting tool reaches a predetermined coordinate position on the workpiece specified in a particular move instruction to move the cutting tool in the feeding
direction.
The critical element on appeal was the “amplitude control unit to control an amplitude of the reciprocal vibration by the vibration unit.” The Examiner found that the specification did not adequately describe structure corresponding to the amplitude control unit. Citizen could not point to any structure in the specification and thus argued that the specification inherently described the corresponding structure because configuring “the control of a numerically controlled machine tool capable of imparting vibration to a tool rest to adjust the amplitude of vibration is obviously within the skill of any experienced numerical machine tool designer. Moreover, the capability of controlling vibration amplitude is inherent in almost any numerical control apparatus utilized in a machine tool having a vibration capability.”
It is not surprising that the PTAB agreed with the Examiner following US law. Specifically, the PTAB easily dismissed Citizen’s argument - “Appellant does not identify any specific disclosure in the Specification that one of ordinary skill in the art would understand to be structure corresponding to the vibration control unit.”
So why didn’t Citizen just delete that element from the claim? Because that structure was necessary to carry out one of the purportedly novel aspects of the invention - reducing the amplitude of the reciprocal vibration by the vibration unit while the cutting tool is fed in the feeding direction when the cutting tool reaches a predetermined coordinate position on the workpiece specified in a particular move instruction to move the cutting tool in the feeding direction. Deleting the amplitude control unit would have likely doomed the claim, just under another statutory provision.
So, when entering the US with means claims, the savvy drafter will do more than just delete the “means” - specifically they will make sure the specification discloses example structure. And if priority must be maintained, the original foreign application should also include such structure.