Appeal 2007-1432
Application 09/141,186
Patent 5,549,673
the art and the understanding of a hypothetical person of
ordinary skill in the art at the time of the amendment.
Therefore, in determining whether an alleged equivalent would
have been unforeseeable, a district court may hear expert
testimony and consider other extrinsic evidence relating to the
relevant factual inquiries.
. . . As we have held in the Warner-Jenkinson context, that
reason should be discernible from the prosecution history
record, if the public notice function of a patent and its
prosecution history is to have significance. See id. at 1356
(“Only the public record of the patent prosecution, the
prosecution history, can be a basis for [the reason for the
amendment to the claim]. Otherwise, the public notice function
of the patent record would be undermined.”); Festo [I], 234
F.3d at 586 (“In order to give due deference to public notice
considerations under the Warner-Jenkinson framework, a patent
holder seeking to establish the reason for an amendment must
base his arguments solely upon the public record of the patent’s
prosecution, i.e., the patent’s prosecution history. To hold
otherwise--that is, to allow a patent holder to rely on evidence
not in the public record to establish a reason for an amendment-
-would undermine the public notice function of the patent
record.”). Moreover, whether an amendment was merely
tangential to an alleged equivalent necessarily requires focus on
the context in which the amendment was made; hence the resort
to the prosecution history. Thus, whether the patentee has
established a merely tangential reason for a narrowing
amendment is for the court to determine from the prosecution
history record without the introduction of additional evidence,
except, when necessary, testimony from those skilled in the art
as to the interpretation of that record.
. . . When at all possible, determination of the third rebuttal
criterion should also be limited to the prosecution history
record. . . . We need not decide now what evidence outside the
prosecution history record, if any, should be considered in
- 33 -
Page: Previous 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 Next
Last modified: September 9, 2013