The ’108 patent, on the other hand, presents a separate
claim construction issue. The ’108 patent is not
related to the ’774 patent, but does disclose a purported
improvement to the ’774 patent. ’108 patent col. 1 ll. 21–
31, col. 7 ll. 1–9. While the ’108 patent may incorporate
by reference the ’774 patent as prior art, it does not
change the fact that the patents are not related. The ’108
patent discloses a separate invention, includes a distinct prosecution history, and is supported by a different written description—including Figures 3 and 4 which clearly depict RAM. These distinctions reinforce the well understood notion that claims of unrelated patents must
be construed separately. Texas Digital Sys., Inc. v. Telegenix, Inc., 308 F.3d 1193, 1211 (Fed. Cir. 2002) (citing Abbott Labs. v. Dey, L.P., 287 F.3d 1097, 1104 (Fed. Cir.
2002)) (explaining that a claim of an unrelated patent
“sheds no light on” the claims of the patent in suit).
Because the asserted patents are not related, the ’108
patent requires a new claim construction inquiry and the
court therefore erred in applying collateral estoppel to the
’108 patent.
