from the United States District Court for the District of
Delaware in No. l:14-cv-00599-SLR-SRF, Judge Sue L. Robinson.
P. Maurer, Williams & Connolly LLP, Washington, DC,
argued for plaintiff-appellant. Also represented by Sanjiv
Prakash Laud, Craig D. Singer.
B. Blumenfeld, Morris, Nichols, Arsht & Tun-nell LLP,
Wilmington, DE, argued for defendant-appellee. Also
represented by MICHAEL J. FLYNN; Mark I. KOFFSKY, EFREM
Schwalb, Koffsky Schwalb LLC, New York, NY.
Prost, Chief Judge, Reyna, and HUGHES, Circuit Judges.
case is about disavowal of claim scope. The specification and
prosecution history of Poly-America, L.P.'s
("Poly-America") U.S. Patent No. 8, 702, 308
("'308 patent") contain clear and unequivocal
statements that the inventor intended to limit the claimed
invention to a trash bag with "short seals" at its
upper corners that extend inwardly to narrow the bag's
upper opening. In light of the inventor's disavowal, the
district court correctly construed the term "short
seal" to require that such seals extend inwardly. We
'308 patent is "directed toward an improved
construction of an elastic drawstring trash bag."
'308 patent col. 3 11. 46-47.
Id. fig. 1.
claimed apparatus is made from two "panels" of
polymeric material joined at the sides and the bottom to form
an enclosed bag. At the bottom, the panels are joined by a
"bottom fold." At the top, a piece of each panel is
folded over and sealed to form a "hem." Inside each
hem is a drawstring. See id. col. 3 11. 46-54.
patent identifies two different seals located along the sides
of the bag. The long seals along the length of the panels are
referred to as "side seals." Id. col. 4
11. 66-67. The small seals in the upper corners of the bag
are referred to as "short seals." Id. col.
5 11. 25-30. The short seals bind together each panel's
hem and the ends of the drawstrings located therein.
principal feature of the claimed invention is
Poly-America's use of inwardly extended short seals to
reduce the width of the trash bag's upper opening. When
coupled with elastic drawstrings, the narrowed opening allows
those drawstrings to wrap around the rim of a trash
receptacle more securely than prior art trash bags that do
not have a narrowed upper opening. See id. col. 6 1.
32-col. 71. 19.
its written description, the '308 patent indicates the
significance of the extended short seal feature and the
reduced upper opening width the extended short seals provide.
To start, the title of the invention is "Reduced ...