View source for Warner-Jenkinson v. Hilton Davis Petitioner Brief Notes

WARNER-JENKINSON COMPANY, INC., Petitioner,

Our position is that the invention protected by the federal patent monopoly cannot go beyond what the patentee has told the PTO (and hence the public) its invention is.

The Federal Circuit, in fundamental disagreement, held that the scope of the protected “invention” is not determined by interpreting the patentee's own statement of its invention. After such interpretation is exhausted, the inquiry-then proceeds to an independent assessment of the scientific facts to determine what changes from the patentee's asserted invention would make a “substantial difference.” 

lower ph levels would cause ”tremendous foaming problems in the plant.”

Limiting non-literal infringement to what is disclosed by the patentee serves fundamental patent policies.

so that other inventors need not conduct independent experiments even to figure out the scope of the patentee's monopoly. Here, without such experiments, no one could have known whether, when industrial volumes of dye were used (cf. Resp. Br. 5 n. 5, 34 n. 24), the filtering process would function equivalently with a ph of less than approximately 6.0

patentee may not recapture through the doctrine of equivalents what it provably dropped from its asserted coverage by narrowing amendments made at the insistence of the PTO, because such amendments constitute a surrender of coverage that makes clear what was not part of the asserted (and approved) invention.

The inescapable addition of substantial systemic uncertainty as to patent boundaries (cf. Chiron Br. 19-20 (noting claim construction not perfectly precise)) is not the only problem with Hilton Davis's policy argument for departing from the meaning of the patent disclosure, which rests ultimately on an appeal to fairness and the basic patent-law policy of providing an adequate reward for the patentee's contribution to knowledge. 

harm to public if scope not adequately defined because waste time, resources experimenting, etc just to find out what actual scope is.