## United States Court of Appeals for the Federal Circuit

05-1001,-1376 PRIMOS, INC., Plaintiff-Appellee,

v. HUNTER’S SPECIALTIES, I NC. and DAVID FORBES, Defendants-Appellants, and WAYNE CARLTON and CARMEN FORBES, Defendants.

Brett L. Foster , Holland & Hart LLP, of Salt Lake City, Utah, argued for plaintiffappellee. With him on the br ief were L. Grant Foster and Mark A. Miller

. Edmund J. Sease , McKee, Voorhees & Sease, P.L.C., of Des Moines, Iowa, argued for defendants-appellants. With him on the brief was Jeffrey D. Harty

. Appealed from: United States District C ourt for the Northern District of Iowa Chief Magistrate Judge John A. Jarvey

## United States Court of Appeals for the Federal Circuit

05-1001, -1376 PRIMOS, INC., Plaintiff-Appellee,

v. HUNTER’S SPECIALTIES, I NC. and DAVID FORBES, Defendants-Appellants, and WAYNE CARLTON and CARMEN FORBES, Defendants.

_____________________ DECIDED: June 14, 2006

_____________________ Before NEWMAN, LOURIE, and PROST, Circuit Judges

. LOURIE, Circuit Judge. Hunter’s Specialties, Inc. and David Forb es (collectively “Hunter’s Specialties”) appeal from the judgment of the United States District C ourt for the Northern District of Iowa of literal infringement, willfulness, and inducement of infringement as to U.S. Patent 5,520,567 and infringement under the doctrine of equivale nts as to U.S. Patent 5,415,578. Hunter’s Specia lties also appeals from t he court’s decision denying a motion for a new trial. Primos, Inc. v. Hunter’s Specialties, Inc. , No. C01-004 (N.D. Iowa Sept. 9, 2004) (“ Final Judgment ”). Because we affirm the district court’s claim construction of the term “engaging,” we also affirm the court’s judgment of literalinfringement of the ’567 patent . Becaus e we conc lude that the applicat ion of the doctrine of equivalents was prope r, we affirm the court’s judgm ent of infringement of the ’578 patent under the doctrine of equivalents. Because the court did not abuse its discretion in excluding evidence, and the c our t’s adverse-inference jury inst ruction did not constitute prejudicial error, we affirm the court’s decision d enying a n e w trial on those issues. BACKGROUND This appeal involves the ’578 pat ent and its continuation, the ’567 patent, which are assigned to Primos, Inc. (“Primos”) and entitled “Game Call Appar a tus.” The patents dis c lose a diaphragm m outh call that hunters use to simulate animal sounds. Figure 1, shown below, is an embodiment of the invention:

As depicted in that figure, the diaphragm mouth call 10 consists of a frame 18, a membrane 22 that vibr ates to produce sound, a flexible peripheral edge 12, and a shelf or plate 15 extending above the membrane. The diaphrag m mouth call is pla c ed completely within the user’s mouth, with the free-end of the membrane pos i tioned near the opening of the mouth. ’578 patent, col. 2, ll. 62-64. The us er holds th e diaphragm in place with his or her tongue, while forci ng air to travel through a gap between the

05-1001, -1376 2tongue and the membrane. The air causes the membrane to vibr ate and to emit a sound that replicates a particular animal. Id. at col. 1, ll. 31-38. T he sound produced by the call is affected by t he tongue pressure applied to the membrane and the distanc e between the membrane and t he r oof of the mouth. Id. at col. 1, ll. 38-40. The patented diaphragm mouth call claims an improvement over prior mouth call devices in that the shelf or plate provides a constant dist ance above the membrane and resists upward pressure by the tongue. Id. at col. 2, ll. 15-26. Relev ant to this appeal are claim 2 of the ’578 patent and claim 21 of the ’567 patent. Claim 2 of the ’ 578 patent reads as follows: A game c a ll apparatus to be c o mpletely inserted inside a person’s mouth for calling game, comp rising: a frame; a membrane of material stretched over the frame; a flexible and moldable peripher al edge e x tending out wardly from the frame; and a plate hav ing a length , the plate extending generally upward from the frame and over a porti on of the membrane, the plate being differentially spaced above the portion of the membrane at various locations along the length of the plate. ’578 patent, col. 4, ll. 45-55 (emphases added). Claim 21 of the ’567 patent reads as follows: A game call for use inside a person’s mouth, comprising: a U-shaped frame; a yieldable reed spanning across the U-shaped frame; a first roof-of-mouth engaging yieldable sealing portion carried by the frame; a second roof-of-mouth engaging portion extending upwardly from the frame, the second portion bei ng spac ed away from the first portion, the first and second por tions defining a predetermined orientation of the U-s haped frame insider the mouth relative to the roof of mouth. ’567 patent , col. 6, ll. 20-32 (emphases added).

05-1001, -1376 3On January 24, 2001, Primos filed suit against its comp etitor, Hunter’s Specialties, alleging that H unter’s Specialties’s accus ed device, known as the Tone Trough, inf r inged Primos’s patents. The a ccused T o ne Trough is a diaphr agm mouth call devic e that, among other features , contains a dome extending above the membrane, instead of a shelf or plate, as claimed in Pr imos’s patents. Primos subsequently amended its complaint, alleging that individu al defendant David Forbe s induced infringement of its patents. 1 Primos initially moved for summary judgm ent of literal infringement and for a preliminary injunction against Hunter’s Specia lties. Hunter’s S pecia lties f iled severa l cross-moti ons, including for summary judgm ent of noninfringement, both literally a n d under the doctrine of equivalents. On July 24, 2002, the court d enied all the motions filed by bot h parties. In its decis ion, the co urt construed the term “p late” in claim 2 of the ’578 patent to mean “a stru ctural element of relatively uniform thickness and flatness which may also have some mo derate curvature to it.” Primos v. Hunter’s Specia lties , No. C01-004 MJM (N.D. Iowa July 24, 2002) (“ Summary Judgment Order ”). Rely ing on that construction of the term “plate,” the court found that “reasona ble minds could differ as to the presence or absence of a ‘plate’ in the Tone Tr ough” and thus denied all summary judgment motions relat i ng to infringement of the ’578 patent. Id. Regarding claim 21 of the ’567 patent, the court not ed that while the te rm “second-roof-of-mouth engaging portion” is not in disput e, it stated that “it is clear that this language requires

1 The amended complaint als o incl uded allegations agai nst individuals Carman Forbes and Wayne Carlton for i nduc ing infringement. The court dismissed Carman Forbes from the case prior to tria l, and it ultim a tely vacated judgment against Wayne Car l ton. Thus, only David Forbes and H unter’s Specialties re main as parties to this appeal.
05-1001, -1376 4that a porti on of the claimed dev ice . . . come into contact with the roof of the user’s mouth while in use.” Id. , slip op. at 43. The court then determined that there were genuine is sues of material fact relating to whether the Tone T r ough device operates when touc hing the roof of a user’s mouth, and therefore denied t he summary judgment motions relating to infringem ent of the ’567 patent. Hunter’s Specialt ies then requested a Markman hearing to interpret the term “engaging” in claim 21 of the ’567 patent. On March 15, 2004, the court cons trued that term to mean to “com e into cont act with.” P r imos v. Hunter’s Sp ecialties , No. C01-004 (N.D. Iowa Mar. 15, 2004) (“ Claim Construction Order ”). The court rejected Hunter’s Specialties ’ construction of the term “engaging” as “interlocking, ” noting that while the word “interlocking,” as defined in a stand ard dictionary, may be appropr iate in the context of a transmission or a la tch, it is not approp riate in the context of the roof of one’s mout h. The court also observed that t he specification of t he ’567 patent did not support a construction of “enga ging” to m ean “interlocking” bec ause the figures in the patent did not provide any means with whic h the diaphragm mouth call could interlock in the roof of a mouth. Accord ing to the court , it had previo usly interpreted “engaging” to mean “to come into contact with,” and it saw no reason to modify that construction. Hunter’s Specialties again m o ved fo r summary judgment, asserting that prosecution history estoppel bar red the application of the doc tri ne of equiv a lents as to the ’578 patent in light of our intervening decision in Festo Corp. v. Shoketsu Kinz oku Kogyo Kabushiki Co., Ltd. , 344 F.3d 1359 (Fed. Cir. 2003). The court determined that the term “plate” was amended during prosec ution by describing it as “having a length,” but that that amendment di d not narrow the scope of the claim because “all physic a l

05-1001, -1376 5objects have a length.” Primos v. Hunter’s Specialties , No. C01-004 MJM (N.D. Iowa Mar. 12, 2004) (“ Prosecution History Estoppel Order ”). The court also obs erved that the term “plate” was amended to require t hat it be “differentially spac ed” above the membrane, which nar rowed the scope of the claim. Id. According to the court, the subject matter surrendered by that amendm ent involved “objects that are not differentially spaced above the membrane.” Because the Tone Trough contained a dome that was spaced above the membrane and therefore arguably did not fall within that surrendered area, the c ourt denied summary judgment of no infringem ent under the doctrine of equivalents as to the ’578 patent. Finally, before trial, Primos filed a motion requesting t hat a devic e known a s the Aluminum Flap Call not be intr oduced as evidence during trial. The court granted that motion, and noted in its order that, throughout discovery, H unter’s Specialties neve r identified the Aluminum Flap Call as invalid ating prior art. Primos v. Hunter’s Specia lties , No. C01-004 MJM (N.D. Iowa Mar. 12, 2004) (“ Aluminum Flap Call Order ”). Hunter’s Specialties had soug ht to introduce the Aluminum Flap Ca ll device when it claimed it had found the dev ice, which was approximately thr ee months prior t o trial and several months after discovery had closed. Ho wev e r, Hunter’s S pecia lties faile d to offer any explanation why it could not locate the Aluminum Flap Call during disc overy. In light of those circumstances, the court determined t hat allowing the Alum inum Flap Cal l to be introduced as evidence during trial would result in unfair surprise to Primos, and thus the court granted Pr imos’s motion to exc l ude the Alumi num Flap Call as evidenc e. A jury trial commenced on Marc h 15, 2004. In the jury instructions conc erning inducement of infringement against indivi dual defendants Wayne Carlton and Dav i d

05-1001, -1376 6Forbes, the court instructed the jury that it could cons ider several factors and stated that “the assertion of the attorney -client privile ge with resp e c t to a non-infringement opinion may support an inference that t he withheld advice of c ounsel wa s adverse to that party.” As for willf ul infring e m ent again s t Hunter’s Specia ltie s, the court did not ins t ruct the jury as to an adverse inference but ra ther stated that the jury mu st consider the “totality of the circumstances.” After a three-and-a-half week trial, the jury found that Hunter’s Specialties ’ Tone Trough device literally infringed the ’567 pat ent, and infringed the ’578 patent under the doct r ine of equi valents. The jury als o found that Hunter’s Spec ialties willfully infr inged the ’567 patent and that David Forbes and Wayne Carlton induced infringement of that patent. Hunter’s Specialties and Wa yne Carlton moved for judgment as a matter of law (“JMOL”), arguing that the c ourt improperly construed the te rm “engaging” in claim 21 of the ’567 patent and that the “all limitations rule” and pr osecution history estoppel barred the application of the doctri ne of equiv a lent s as to the ’578 patent. Those defendants also moved for a new trial, arguing that the court erred in excludi ng the Aluminum Fla p Call as evidence, and that the court’s adverse-inferenc e ins t ruction resulted in prejudicial error. The court denied the moti on for JMOL and the motion for a new trial. Primos v. Hunter ’s S pecia lties , No. C01-004 (N.D. Iowa Mar. 31, 2005). (“ Post-Trial Order ”). In its decision, the court first r eaffirmed its constructi on of the claim term “engaging” in claim 21 of the ’567 patent, noting that it had address e d the same issue in previous decisions. The court next determi ned that t he “all limitations rule” did not preclude the applic ation of the doctrine of equivalents for the ’578 patent, reasoning that the only disputed term was “plate” in claim 2, and that determining that a dome was

05-1001, -1376 7equivalent to a plate did not v i tiate that claim limit ation. The court also held th at prosecution history estoppel did not prevent the applic ation of the doctrine of equivalents as to the ’578 pat ent because the Tone Tr ough did not fall within the area surrendered during prosecution. In addition, the court deni ed Hunter’s Specialties ’ s motion for a new trial, reaffi rming its prior decision that the Aluminum Flap Call device could not be introduced as inv a lidating prior art becaus e it was produc ed after the period for discovery had c l osed. Although the c o urt determined t hat its “adverse inference” instruction to the jury was not in error, the court lat e r vacated judgment against Wayne Carlt on, the only defendant who had asserted the attorney-client privilege, in light of our decis ion in Knorr-Bremse Systeme Fuer Nutzfahrzeuge GMBH v. Dana Corp. , 383 F.3d 1337 (Fed. Cir. 2004) (en banc). Hunter’s Specialties timely appealed to t h is court, and we have jurisdiction pursuant to 28 U.S.C. § 1295(a)(1). DISCUSSI ON We review a district court’ s denial of a motion for JMOL de novo by reapplying the JMOL standard. Markman v. Westview Instruments, Inc. , 52 F.3d 967, 975 (Fed. Cir. 1995) (en banc). We also review t he legal standards that the jury applied in reaching it s verdict to determine whether t hey were correct as a matter of law. Id. at 975. JMOL is appropriate when “there is no legally sufficient evidentiary basis for a reasonable jury to find for that party on that iss ue.” Fed. R. Civ. P. 50(a)(1). The denial of a motion for a new t r ial is an is sue not un ique to patent law; thus , we apply t h e la w of the regional circuit in which the district court sits—in this ca se, the Eighth Circuit. In the

05-1001, -1376 8Eighth Circ u it, the dec ision to deny a motion for a new trial is reviewed under an abus e of discretion standard. Bla i r v. Wills , 420 F.3d 823, 829 (8th Cir. 2005).
I. Cla im Con s truction The question of literal infri ngement of claim 21 of the ’567 patent turns entirely on the district court’s construction of the term “engaging.” Claim construction is a question of law reviewed de novo

. Cybor Corp. v. FAS Techs., Inc. 138 F.3d 1448, 1454-56 (Fed. Cir. 1998) ( en banc). Hunter’s Specialties argues that the court er red in c o ns truing the term “engaging” in the phrase “second roof-o f-mouth engaging yieldable sealing portion” to mean “to come into contact with.” Accord ing to Hunter’s Spec ialties, the proper construction of the term “engaging” is “seali ng” or “interlocking.” As support for its construction, Hunter’s Spec ialties notes that claim 21 uses the word “engaging” to describe a seal created between the edge of the frame and the roof of the user’s mouth. Also, Hunt er’s Specialties obs erves that the specification describes the edge a s “sealing” against the roof of a mouth. In addition, Hunter’s Specialties finds support for its construction in a dictionary definition t hat describes “engaging” as “to come together and interlock.” Hunter’s Spec ia lt ies points out that this def inition is cons istent with the way the term is used throughout the patent. Primos responds that the district c ourt correctly construed “engaging” as “to come into contact with.” According to Prim os, the intri n sic evidence does not support the selective dictionary definit ion put forth by Hunter’s Spec ia lties. In particular, the claims use both terms, “engaging” and “sealing,” and thus each term is presumed to have a dist inct meaning. Also, Primos assert s that to construe “ engaging” as “sealing ” or “interlocking” would ex c l ude a preferred embodiment of the patent because the

05-1001, -1376 9figures in t he patent s how the m e mbrane as not interlocking with the roof of a mouth. In addition, Primos obser ves that while “ i nterlo cking” might be an appropriate construction of “engaging” for an invention relating to mechanical machinery with gears, it is not appropriate in the context of diaphragm mouth calls. We agree with Primos that the distri ct court correctly construed the term “engaging” to mean “to come into contac t with.” As t h is court explained in Phillips v. AWH Corp

. , we ordinarily construe claim t e rms to have their customary meaning as understood by a pers on of ordinary skill in the art. 415 F.3d 1303, 1312-17 (Fed. Cir. 2005) (en banc). In ascertaini ng the ordinary and customary meaning of a claim term, a court’s primary focus should be on t he intrinsic evidence of record, viz. , the claims, the specification, and, if in evidence, the pr osec ution history. Id. Starting with the language of claim 21, the terms “engaging” and “sealing” are both expressly recited in the claim and therefore “engaging” cannot m ean the same thing as “seali ng”; if it did, one of the terms would be superfluous. Turning to the specification, although the word “engaging” is not expressly mentioned in the specificat ion, figures 1 and 3 aid our unders t anding of that term. Figure 3, as depicted below, shows a call de vice positioned in a user’s mouth.

05-1001, -1376 10As shown in the figure above, there are severa l points of contact between the roof of a user’s mouth (the top striped structure in the figure a bove) and the diaphr agm mouth call—one s u ch point is with the plate 24 and anot her is with the per ipheral edge of the frame 12. That figure show s the plate touching the roof of the mouth, but does not reveal an interlocking relationship because there is no depicted m eans from which the frame can “interlock” wit h the roof of a user’s mouth. The figure therefore supports a construction of “engaging” as to “come into cont act with,” while disc ouraging a construction of “interlocking.” While we are mindful that we c annot import limitations from the preferred embodiments into the claim, we als o should not normally interpret a claim term to exclude a preferred embodiment. See Burke, Inc. v. Bruno Indep. Living Aids, Inc. , 183 F.3d 1334, 1341 (Fed. Cir. 1999). Interpreti ng “engaging” to mean “interlocking” would exclude the embodiment s hown in the figure and is not consistent with the rest of the specific ation whic h does not suggest an interlocking relations hip between the roof of a m outh and the mouth call. 2 We therefore agree that the district court’s construction of the term “engaging” to mean “to come into contact with” is supported by the intrinsic record and is correct.
II. Doctrine of Equivalent s Hunter’s Specialties c hall enges t he applicat ion of the doc trine of equivalent s on the ground that prosecution his t ory estoppel applies to the term “plate.” Hunter ’s Specialties specifically asserts that amend ments to the term “plate” narrowed the scope of the cla i m and were made for reasons re lating to pa tentability. A ccordin g to Hunter’s Specialties, prosecution hist ory estoppel therefore barred t he doctrine of equivalents for

2 We do not discuss the prosecution hist ory here becaus e it is not r e levant to the construction of the term “engaging.”
05-1001, -1376 11that claim term. Primos responds that the district court properly applied the doctrine of equivalents

. It reasons t hat the first amendment made to the term “plate”—that it include a “length”—did not narro w the sc ope of the claim. As to the second amendment made to the term “plate”—that it be “diffe rentially spac ed” above the membrane—that amendment bears no more than a tangential relations hip to the ac cused Tone Trough. In particular, Primos contends that the terri tory surrendered by that amendment consists of objects that are not diffe rentially spaced above the memb rane. Because the accused device’s “dome” is differentia lly spaced above the m e mbrane, Primos ass e rts that the “differentially spaced” amendment does not pertain to the disputed element in the accused device and it is therefore merely tangential to the accused device. According to Primos, prosecution histor y estoppel thus does not apply to pr event the applic ation of the doctrine of equivalents here. We agree with Primos that t he district court correctly determined that prosec ution history estoppel does not apply here to pr eclude the application of the doctrine of equivalents

. As the S upreme Court explained in Festo , when a pat ent claim is amended during prosecution for reasons relating to pat entability, there is a presumption that the patentee surrendered a ll the territory between the or iginal claim limitation and the amended claim limitation. 5 35 U.S. at 740. T here are s i tuations, however, in whic h a patentee may overcome that presumption. Id. One such situation is when the “rationale underlying the amendm ent may bear no more than a t angential r e lation to the equivalent in question.” Id. at 740-41. The term “plate” in claim 2 of the ’ 578 patent was amended in two ways: ( 1 ) by requiring that it hav e a “le ngth” and (2) by adding the limitation that the plate be

05-1001, -1376 12“differentially spaced” above the membrane. Th e district court correctly recognized that the addition of the term “lengt h” did not narrow the scope of the claim bec ause every physical object has a length. The district court also determined that adding the limitation t hat the plate be “differentially s p aced” abov e the membrane did narrow the scope of t he claim, and the court assumed that the reason for the amendment was a substantial one relating to patentability. We agree with the district court, however, that the territory surrendered by the “differentiall y spaced” amendment comprises plates that are not diff erentially s paced abo ve the membrane. T hat conc lusion is consistent with the prosecution history. T he patentee added the “differentia lly spaced” limitation to distinguish the diaphragm mouth call from a prior art device that consisted of a shelf-like structure positioned on top of the membrane without any spacin g. The accus ed dev i ce, however, includes a dome that is spaced a bove the membrane. Because the accused device’s dome includes the spacing, t he amendment was merely tangential to the contested element in the a ccus ed dev ice, and thus prosec ution history estoppel does not apply to prevent the application of the doctrine of equivalents. Hunter’s Specialties also argues that the court s hould not have allowed the application of the doctrine of equivalents because, by doi ng so, the claim limitation “plate” in claim 2 of the ’578 patent was vitiat ed. According to Hunter’s Spec ialties, the court’s construction of the term “plate” require s a specific structure “of relatively uniform thickness and flatness whic h may also hav e so me m oderate curvature to it. Hunter’s Specia lties asserts that allo wing a “dome” to be considered an equivalent to a “plate” would eliminate that lim itation from the claim. Primos responds that the “all limitations rule” is not applicable t o the c i rcumstances in this c a se. According to Primos, the term

05-1001, -1376 13“plate” does not convey a definit ive, geometri c shape or structure, and thus that claim limitation was not vitiat ed. Prim os asserts that the district c ourt properly allowed the jury to consider whether a “dome” was equivalent to a “plate” and that in doing s o , no claim limitation was eliminat ed. We agree with Primos that the application of the doctri ne of equivalents was not improper in this case. Under the doctrine of equivalents, “a product or process that does not literally inf r inge upon [sic] th e express terms of a patent claim may nonetheles s be found to infringe if there is ‘equivalenc e ’ bet ween the elements of the accused product or process and the claimed el ements [sic] of the patented invention. ” Warner-Jenkinson Co., Inc. v. Hilton Dav i s Chem. Co. , 520 U.S. 17, 21 (1997) (citation omitted). The “all limitations rule” restricts the doctrine of equivalents by preventing its application when doing so would vitiate a claim limitation. Warner-Jenkinson , 520 U.S. at 29 (stating that the doctrine of equival ents cannot be applied broadly so as to “effectively eliminate that [cla im] element in its entirety”); Lockheed Martin Corp. , 324 F.3d at 1321 (“[I]f a court determi nes that a fi nding of in fringement under the doctrine of equivalents ‘would ent irely vitiat e a particular claim element,’ then the court should rule that there i s no infringement under the doctri ne of equiv a lents.” (citation omitted)). On appeal, Hunter's Specialtie s argues that we should reverse the jury’s finding of equivalence because the substitution of the accused dome for the claimed “plate” would vitiate the “plate” limit ation and thereby violate the all lim itations rule. As the district court recognized, Hunter’s Specialtie s is ess e ntially c ontending that there can be no equivalent to the claimed “p late.” Our precedent has rec ognized that “[t]here is no set formul a for determining whether a findi ng of eq uivalence would vitiate a claim

05-1001, -1376 14limitation, and thereby violate t he all limitations rule. Rather, courts must consider the totality of the circumstances of each case and determine whether the allege d equivalent can be fairly characterized as an insubstant ial change from the cl aimed subject matter without rendering the pertinent limitation meaningless. ” Freedman Seating Co. v. Am. Seating Co. , 420 F.3d 1350, 1359 (Fed. Cir. 2005) (cit ations omitted). Thus, because Primos’s theory of equivalence ( i.e. , that a dome is equivalent t o the c l aim ed “plate”) does not “effectively eliminate . . . [the ‘plate’ lim itation] in its entiret y,” it does not violate the all limit ations rule. Noting that Hunter’s Spec ialties has not c hallenged whether the jury’s finding is suppor ted by substantial evi dence, we affirm the jury’s finding that the accused dome is equivalent to the claimed “plate.”
III. Exc l usion of Evidence Hunter’s Specialties next ar gues that the district cour t abused its discretion in

exc l uding a prior art device, the Aluminum Fl ap Call, from evidence becaus e admitting it would hav e resulted in prejudicial surprise. According to Hunter’s Specialties, even though the device its e lf was not located unt il shortly before tri a l began, Primos was aware of it as being potentia l prior art throughout discovery . For example, Hunter’s Specialties asserts that defendant Wayne Carlton was extensively questioned by Primos on the Aluminum Flap Call device. Hunter’s Specialtie s also asserts that Primos waited until shortly before the commencement of trial to claim prejudicial sur p rise, even though it knew about the device much earlier. In addition, Hunter’s Specialties argues that there is a str ong public policy in favor of allo wing the Aluminum Flap Ca ll as evidenc e because the public interest requires consideration of any invalidating prior art device.

05-1001, -1376 15Primos responds that the di strict court properly exclu ded the Aluminum Flap Call because Hunter’s Specialties nev er identified that device as potentially invalidating prior art during discovery. In addition, Primos a sserts that the defendant s did not provide an explanation as to why they could not locate that device during disc ov ery. According to Primos, to permit the Aluminum Flap Call to be introduced as ev idence during trial, after years of discovery during which t hat device was not identified, would result in prejudicial surprise. Also, although the Aluminum Flap Call may have been mentioned durin g discovery, its origin c ould not be authentic ated, and the testimony revealed that the prototypes were experimental in nature. Thus, there was no reason for Primos to believe that the Aluminum Flap Call was prio r art and would be intr oduced as evidenc e

. We agree with Prim os that the distri ct c ourt did not abuse its discretion in

exc l uding t he Aluminum Flap Call from evidence. The record reflects that the Alumin um Flap Call was not located unt il after discovery had closed. M o reover, although the Aluminum Flap Ca ll may have been mentioned during disc overy, it was never identified to the court as an inv a lidating pr ior art devic e. The district court prevented Hunter’s Specialties from introducing the Aluminum Fl ap Call into evidence becaus e it “did not demonstrate dilig ence in attempting to loca te the call during disc overy” and becaus e during disc overy Hunter’s Specia lties did not assert that it was claiming the Aluminum Flap Call as invalidating prior ar t. That determination was not an abuse of discretion. It was well within the district court’s provin ce to determine that because the Aluminum Flap Call was not identified as potential prior art u n til after discovery had closed and shortly bef ore trial commenced, it would th en be unfair to permit its introduction int o evidenc e.

05-1001, -1376 16We reject Hunter’s Specia lties’ argument that policy c oncerns should override the district court’s decision to ex clude the Aluminum Flap Call as evidence. First, and most importantly, the court never determined whether the Aluminum Flap Ca ll was in fact invalidating prior art, and the parties disput e whether the device wa s in public use— it
was assert ed that its use was experimental and occurred only in Canada. Thus, the Aluminum Flap Call may in fact not have been invalidating prior art at all. Second, as the district court point ed out, the purpose of discovery is to enable parties to obtain the factual information needed to prepare their cases for trial. The district court mus t therefore consider the “unfair and prejudicial surprise” to a party that may result from allowing ev idence to be presented during trial. See AT D Corp. v. Lydall, Inc. , 159 F.3d 534, 551 (Fed. Cir. 1998) (stating that the pur pose of both the Federal Rules of Civ il Procedure and 35 U. S.C. § 282 is to prev ent unfair and pr ejudicial s u rprise and not t o permit last-minute production of evidenc e). The distric t cour t determined that Hunter’s Specialties had ample opportunity to introd uce the Aluminum Flap Call dur ing the two and a half year discov e ry phase. Because it did not do so, t he district court w a s entitled to decide t hat Hunter’s Spec ialties may no t then introduce disput ed evidence beyond the time allotted for discovery.
IV. Adverse-Inference Jury Instruction Finally, Hunter’s Spec ia lties asserts that under Knorr-Bremse , 383 F.3d at 1337, the district court erred in instructing the jury that it could draw an adverse-inference from an opinion withheld due to the assertion of the attorney-client privilege. Although Hunter’s Specialties recogniz e s that the only defendant to assert the attorney-client privilege was Wayne Carlton, it argues that the adverse-inference jury instruction

05-1001, -1376 17prejudiced all defen dants becaus e the infringement clai m involved all defendants and was tried to one jury. Primos responds th at the court vacated the judgment agains t Wayne Carlton, the only indi v i dual who asserted the atto rney-client privilege and therefore the only per son who wa s potentially prejudic ed by the j u ry instruction. Primo s points out that Hunter’s Spec ialties waiv ed the attorney-cli ent privilege and thus was not affected by the adverse jury instruction. In addition, Primos contends that Hunter’s Specialties did not present any evidenc e on how it was prejudiced by the jury’s instruction. We agree with Primos that the jury in struction did not prejudice Hunter’s Specialties. A party seeking to alter a ju dgment bas ed on erroneous jury instructions must establish that “those instructions were legally erroneous,” and that “the errors had prejudicial effect.” Advanced Display Sys., Inc. v. K ent State Univ. , 212 F.3d 1272, 1281 (Fed. Cir. 2000). Legal error in an erroneous jur y instruction is prejudicial when it is “inconsis tent with substantial justice.” Fed. R. Civ. P. 61. The jury’s instruction for inducement of infringement against individual defendants Dav i d Forbes and Wayne Carlton provided that “the assert ion of the attorney-client pr ivilege with respect to a noninfringement opinion may support an inference that the withheld adv ice of c ounsel was adverse to that party.” That jury instruct ion thus permitted an adverse inference to be drawn against the party that asserted the atto rney-client privilege. The only individua l who ass e rted the attorney-client privile ge, h o wever, was Wa yne Carlton, and the court vacated the judgment of induc em ent of infringement against hi m. The only indiv i dual therefore potentially prejudiced by the adverse-inf erence instruction was Wayne Carlton, not Hunter’s Specia lt ie s. In addition, in the jury’s instruction as to willful

05-1001, -1376 18infringement against individual defendant Hunt er’s Specialties, the expre ss adverse inference language was absent. Rather, the instruction st ated that the jury must consider t he totality of the circumstances and may rely on a number of factors to support a finding of willfulness. T here was t herefore no adverse-inference ins t ruction as to willfulne ss against Hunter’s Spec ia lties. Thus, we conclud e that the jury’s instruction was not legally erroneous and did not result in prejudicial e rror against either indiv i dual defendants Hunter’s Specialt ies or David Forbes. We have c onsidered Hunter’s Specialties other arguments and fi nd them to be unpersuasive. CONCLUS ION Because the court properly const r ued t he term “engaging,” we affirm the court’s judgment of literal infringemen t. Because the claim term “pla te” is a structure that was not vitiated by substitution of a dome, we affirm the court’s conclusion that applying the doctrine of equivalents was not improper. Also, bec ause the amendment was merely tangential to the contested el ement in the accused device, we affirm the court’s determination that prosecution history estoppel did not preclu de the applic ation of the doctrine of equivalent s. Finally, because t he court did not abuse its dis c retion in

exc l uding t he Aluminum Fl ap Call as ev idence and bec aus e its adver se-inference instruction did not constitute prejudicial error, we affi rm the court’s decis ion deny ing a new trial.
AFFIRMED

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