Most readers who are patent litigators will know this already, but a "claim chart" is a table with two columns. The column on the left lists claim elements, and and the column on the right lists the portions of something—typically a product, system, or disclosure—that meets the elements on the right.
The chart shows the reader how the thing (whatever it may be) meets the elements of a claim or claims.
Detailed claim charts sometimes include figures with arrows pointing to the relevant claim elements, quotes of relevant text (if applicable), and/or a narrative description of how the cited material meets the element.
Of course, one risk in doing a claim chart is that, if you are too specific, you may make it too easy for the other side to rebut your arguments. It's often advantageous to keep things somewhat flexible, while still disclosing enough to serve the purpose of the chart (typically supporting a complaint, or infringement or invalidity contentions). There's an art to it.
Sometimes, rather than charting a product or reference, a party will just describe how it meets the claim elements. This can provide another level of abstraction and flexibility, and it can also be easier to read and understand. But, obviously, it typically won't be as detailed as a claim chart.
This week, Judge Fallon unsealed an opinion from last month that dealt with whether that kind of narrative description is sufficient to disclose a reference in final invalidity contentions, such that an accused infringer's expert could later rely on it for anticipation and obviousness.
The Court held that yes, a narrative description can suffice to allow an expert to later offer a report with detailed opinions regarding how the reference meets the claim elements:
Samsung's final invalidity contentions broadly state that the asserted patent claims "are anticipated or rendered obvious" by the MSM6250 chipset and other prior art devices. . . . The final contentions present a theory of anticipation in a narrative description of how the MSM6250 chipset meets each claim limitation of the asserted claims in U.S. Patent No. 7,532,865 ("the '865 patent"). . . . This disclosure is sufficient to put TOT on notice of Samsung's theory of anticipation by the MSM6250 chipset.
TOT Power Control, S.L. v. Apple Inc., C.A. No. 21-1302-MG, at 17 (D. Del. Apr. 30, 2025).
Judge Fallon rejected the idea that a party has to include a claim chart in its invalidity contentions:
TOT's position that Samsung's disclosure in its final invalidity contentions must take the form of a claim chart with detailed source code analysis and citations is not supported by analogous case authority. In Speyside Medical, LLC v. Medtronic Corevalve, LLC, the court acknowledged that "a party is not required to cite every piece of evidence that will be used to support a given theory" in its invalidity contentions, and "it is proper for an expert to expand upon such theories in his expert report." (C.A. No. 21-1305-MN, D.I. 257, Ex. 2)
Id. at 17 n.7.
The narrative description, however, apparently only addressed anticipation and obviousness generally, not specific combinations. The Court held that the specific combinations that the expert later charted had not been adequately disclosed:
However, there is no dispute that Samsung's final contentions do not disclose the MSM6250 chipset in combination with other prior art references for purposes of an obviousness analysis. . . . Samsung's failure to chart the MSM6250 chipset in combination with other prior art references in its final invalidity contentions is inconsistent with the intended purpose of final contentions.
Id. at 17.
The Court ultimately permitted even those undisclosed combinations, though, under the Pennypack factors. It held that the patentee had failed to show prejudice, that any prejudice was cured by the patentee's responsive expert report, that there was no bad faith, and that the combinations were important. Id. at 18-19.
Of course, I would not read this case as saying that narrative descriptions are fine in all instances, and that an accused infringer can freely withhold obviousness combinations from its final invalidity contentions. It's always going to be a question of risk, and in practice the Pennypack factors seem to give judges significant flexibility in deciding whether to strike things.
If you enjoyed this post, consider subscribing to receive free e-mail updates about new posts.
