I just got logged back on JA. Been very busy and still very busy.
Yes, the logic does work "backward" if prior art has "at least one of" in a list of items then the limitation has been done before in the prior art.
Question 1: I have a claim that looks like this:
2. The device of claim 1, wherein said image is visible in 3-D due at least in part to at least one of
1) said display directs different images to different eyes supporting stereopsis,
2) video voodoo1 or
3) video voodoo2.
Everybody and his inbred cousin does “1)” since that’s how all 3-D has worked up till now. Does including one element in my list that’s old art destroy the claim like it appears to have done to Mr. Brown? Yes/No ___.
YES - for such limitation. For validity purposes regarding what has been done in the prior art, adding one old "technology" in a list of new technology (using "at least one of") "zaps" that limitation. The claim may still be valid but such will depend on whether or not there are other limitations that are novel and thereby "save" the claim.
Question 2: It’s good to know that one element in an “at least one of…” list within a claim can be bogus without destroying the applicability of the list!
Similarly, if one PARAGRAPH in the claim below isn’t true (guess which one) can the claim still be valid?
2. The device of claim 1, wherein the number of ball bearings is doubled to reduce the load on each individual ball bearing; and the world is saved by the superior plastic ball bearings.
You ask about "the claim" and I will assume such refers to "Claim 1".
As to Claim 1, claim 2 is a "dependent claim" as it depends from claim 1. A dependent claim cannot typically affect the validity of the claim from which it depends.
If Claim 1 was valid before claim 2 the claim 1 is likely still valid. I can think of one very limited and unlikely exception but otherwise claim 1 is still valid.
IF you are referring to Claim 2, the limitation "the world is saved by the superior plastic ball bearings." would not make it past the Examiner. If it did, is the claim valid?
The answer depends on what type of problem the bad clause embodies. If the bad clause is clearly not enabled by the specification then Claim 2, and all claims that depend from claim 2 are not enabled, and thus, invalid.
If claim 2 has a simple scrivener's type error the courts will likely overlook such error.
IF claim 2 contains the type of error that (after reading the specification or in light of the specification) the meaning of the claim can be determined in a way to save validity, then the courts will often uphold the validity of the claim.
Claim construction and validity are very fact specific questions and one answer rarely fits all questions.
If, in fact, the last line is bad science and won’t happen (not sure if the world can be saved by ball bearings), is the true part of claim 2 still a valid claim (and the dependent claims dependent on claim 2 are good too) as long as one of the multiple claim lines is good? (Is there an MPEP reference on this?)
NO. Think enablement. The specification (written description, drawings, etc.) must teach and enable every REQUIRED limitation of a claim (must teach one of ordinary skill in the art to make and use the invention). IF a REQUIRED claim limitation is impossible (like time travel - as far as we know) then the claim cannot be enabled by the specification and is invalid.
Example: suppose m, n possible, o is not possible.
X as in claim 1, wherein B is at least one of m, n, and o.
IF m and n are enabled by the specification but not o, claim is still valid.
X as in claim 1, wherein B comprises m, n, and o.
IF m and n are enabled by the specification but not o, claim is invalid and all claims that depend from claim 1 is invalid.
Please keep asking questions until you are satisfied.