Wednesday, March 3, 2010

Case law you can use: functional equivalent not enough for anticipation

Takeaway: When structure is claimed, a reference used for anticipation must disclose the claimed structure, not merely a structure that performs the same function. See In re Ruskin, 347 F.2d 843, 846 (CCPA 1965).

I first came across the "no functional equivalents" doctrine in the Appellant's brief for a mechanical case, Ex parte Konstant. One of the claim elements at issue in Konstant was a "flange ... with the entire upper width that defines an upper support for at least one cross bar." Citing to a dictionary, the Examiner asserted that a flange was "a projection used for strength or attachment," then asserted that "the 'steps' or 'lips' of [the reference] perform this function." The Appellant cited Suzuki v. Richardson for the proposition "for anticipation, 'almost' is not enough; there is no such thing as 'anticipation by equivalents'."

I thought it was an interesting argument, though the Board in Konstant didn't mention the doctrine and instead reversed on other grounds. (Namely, it's improper for Examiner to rely on the same structure to disclose two separate claimed elements; see my Ex parte Konstant post here).

I was excited to see the BPAI using what seems to be the same "no functional equivalents" doctrine in Ex parte Kershaw. I found out about this decision on the Florida Patent Lawyer blog. You should read Mike Terry's post (here) for the details, but here's my take on it. The Appellant claimed a memory management unit, and the Board found that the Examiner's reliance on software components that perform memory management was misplaced since the claimed unit was a structure (i.e., hardware):
[T]he Examiner appears to be relying on certain memory management function performed by various software components in Ledebohm (e.g., Driver Program 136, and/or Resource Manager 138). (See FF2.) We agree that Ledebohm is directed to performing management functions. However, we note that functional equivalence is not enough to show anticipation of a structural component (such as the claimed memory management unit). See In re Ruskin, 347 F.2d 843, 846 (CCPA 1965) (“the functional equivalent is not enough to be a full anticipation of the specific device claimed by appellant.”)
(Ex parte Kershaw, p. 8.)
While most of the applications I work on involve a lot of function rather than structure, when I do have a structural element I'm definitely going to watch out for an opportunity to apply In re Ruskin.


  1. This is wonderful! Thank you.

  2. Isn't that just delaying the inevitable, though? I agree that it's an argument that must be made to protect the record, but the Examiner will just come back with a 103 rejection using the same art, so I'm not as excited about it.

  3. >the Examiner will just come back with a 103 rejection using the same art

    Agreed. But a 103 gives you options that aren't available in a 102, right?

    I see a couple of fact situations where In re Ruskin might be most appropriate. One, when you have arguments why it would *not* be obvious to (borrowing from Ex parte Konstant's facts) replace the "step" in the reference with a "flang" as claimed, even though they perform the same function. Two, when you think the Examiner is wrong about the two structures performing the same function.

    >argument that must be made to protect the record

    I don't know about "must".

    Some folks traverse absolutely everything. Others are strongly averse to making "legalistic" or "technicality" arguments (the "don't piss off the Examiner" approach).

    I see all this as a matter of basic prosecution style/philosophy. I like to think I take the middle ground, making strategic choices for which arguments to present.

    Some might view "no anticipation for functional equivalents" as a legalistic or technicality argument, but I'd probably make it even without good arguments against combining.

    On the other hand, I do not traverse every Official Notice (e.g, not "the earth revolves around the sun") and I do not generally traverse my Background being used as Applicant-Admitted-Prior-Art.

  4. Sometimes it is important to get a 103 rejection rather than a 102 rejection. Doing so might allow applying 103(c) or other non 102 appropriate argument such as teaching away, unexepected results, etc.

    On occasion an examiner resists changing to a 103 rejection because he/she want to go final, If you end up filing a pre-appeal brief conference request in these situtations, this argument may keep you out of that long appeal queue.