Brief context
- I'm in the early stages of product development, pre-prototype. (Subtext: definitely no funds available for a legal opinion. I'll cross that bridge when it becomes feasible; for now, I'm just looking for a better understanding how prior art is generally interpreted in cases like this one.)
- Bad news: there is an unexpired US patent that covers my concept (most claims are relevant and not easily designed around).
- Good news (probably): I've found a few instances of prior art that support strong arguments that the patent is invalid on grounds of not being novel (my own non-lawyerly opinion of course). However, the patent is not a carbon copy of the prior art so there's a bit of room for interpretation.
- The company does not appear to be practicing the patent anymore (nor are there any other companies doing so), so I don't see a need to go out of my way to invalidate it, but I'm doing a bit of homework now in case at some point in the future, the patent holder makes a fuss.
- (I recognize that to show invalidity you have to show "that the patent is invalid by clear and convincing evidence, a substantially greater burden" than proving infringement https://chicagounbound.uchicago.edu/cgi/viewcontent.cgi?article=5529&context=journal_articles)
- (I'll keep this post focused on an issue regarding one instance of prior art; I'll make another post on a different issue regarding another instance of prior art.)
Rather than citing the patent or prior art here, I'll lay out the key issue in general terms.
- I've found a patent (from the 1910s, in case that's relevant), call it Patent A.
- Patent A's claims describe the apparatus in the unexpired patent, call it Patent B. This is thanks to the broad wording of the claims of Patent A, which do not specify the number of wheels on each axle.
- Patent B describes an apparatus with one wheel on each axle.
- The specification of Patent A, however, describes an apparatus with a pair of wheels on each axle. This description makes reference to the drawing which shows "the preferred embodiment".
- Though A's specification does not explicitly refer to alternative embodiments with different numbers of wheels, it does not in any way state that the preferred embodiment is the only possible one.
- (Note: Patent A is not cited in Patent B or its examination.)
It's not clear to me how A's claims would most likely be interpreted.
According to this article http://www.ipbrief.net/wp-content/uploads/2012/10/IPB_Nilforoush.pdf "If the specification describes an embodiment as being its “best mode,” or only describes a single embodiment, the claim should not necessarily be limited to this embodiment, unless other factors suggest there is an implied disavowal of claim scope."
That sounds encouraging for a broad reading of Patent A; but the article discusses different approaches to interpreting claims: "When a court emphasizes “interpreting the claims in view of the specification,” the result is a more liberal use of the specification. Under this approach, the court focuses more on the rule that the specification provides context for the claims, rather than the rule that limitations from the specification should not be read into the claims. ... When the emphasis is on avoiding “improperly reading limitations from the specification into the claims,” the court tries to rely strictly on the claims themselves while minimizing reliance on the written description or other evidence. This approach places more emphasis on the rule that the claims define the scope of the patent right and emphasizes giving claim terms their ordinary and customary meaning, while placing less emphasis on the notion that the specification provides the context for the claims."
Adding to my uncertainty, the MPEP https://www.uspto.gov/web/offices/pac/mpep/s2111.html says that "Patented claims are not given the broadest reasonable interpretation during court proceedings involving infringement and validity, and can be interpreted based on a fully developed prosecution record."
How would Patent A likely be interpreted? My sense (and my hope) is that Patent A should be interpreted for everything it contains, including its broad claims, which describe an apparatus with an unspecified number of wheels per axle (not sure if there's a better word to use here, but you get the idea: it could be 1, 2, whatever wheels per axle).
Do I have the right reading here, or am I missing something? Would this be the most likely interpretation of Patent A (in a scenario where it became necessary to argue that Patent B is invalid)? Or are there additional considerations?