IN THE UNITED STATES DISTRICT COURT

FOR THE EASTERN DISTRICT OF PENNSYLVANIA

____________________________________

:

AGRIZAP, INC., : CIVIL ACTION

:

Plaintiff, :

:

v. : No. 04-3925

:

WOODSTREAM CORPORATION, et al., :

:

Defendants. :

____________________________________:

MEMORANDUM

ROBERT F. KELLY, Sr. J. OCTOBER 19, 2006

Plaintiff Agrizap, Inc. (“Agrizap”) alleges that Defendant Woodstream Corporation

(“Woodstream”) infringed on its U.S. Patent No. 5,949,636 entitled “portable pest electrocution

device with resistive switch trigger” (“636 patent” or “Rat Zapper”). Presently pending before

this Court is Woodstream’s Motion for Partial Summary Judgment of Patent Noninfringement. 

For the following reasons, Woodstream’s Motion is denied in part and granted in part.

I. BACKGROUND

The relationship between Agrizap and Woodstream began in 2000. Woodstream

contacted Agrizap about the possibility of the two parties entering into a marketing and

distribution agreement for Agrizap’s Rat Zapper Product. The Rat Zapper is a rodent control

device that consists of a plastic canister with a metal plate at the bottom and an electrical charge

that ultimately kills the rodent. An oral marketing and distribution agreement was established

between the two parties whereby Agrizap would manufacture and deliver Rat Zappers to

Woodstream and Woodstream would distribute them to various retailers. The Rat Zappers,

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however, would use Woodstream labels. 

According to its Second Amended Complaint, Agrizap discovered in early 2004 that

Woodstream was manufacturing and marketing its own electronic rat trap. Agrizap asserts that

confusion in the retail market developed because of Woodstream’s branding of the Agrizap Rat

Zapper and because of Woodstream’s newly introduced electronic rat traps. Agrizap asserts that

if this continued, Woodstream would effectively undermine Agrizap’s ability to sell its goods in

the market. The Second Amended Complaint contains the following five counts against

Woodstream: Violation of California’s Unfair Business Practices Laws & Professions Code

(Count I); Breach of an Oral Contract (Count II); Patent Infringement (Count III); Intentional

Misrepresentation (Count IV); and Trade Disparagement (Count V). 

This present Motion for Partial Summary Judgment is the third such motion filed by

Woodstream. Woodstream’s first partial summary judgment motion was on Agrizap’s patent

infringement claim and was based on the grounds of patent unenforceability and invalidity. This

motion was denied. Its second motion was on Agrizap’s state law claims. This Court granted

summary judgment as to the California Unfair Business Practices Laws & Professions Code

claims, the breach of contract claim, and the trade disparagement claim, but denied summary

judgment as to the intentional misrepresentation claim. Thus, only the patent infringement claim

and the intentional misrepresentation claim against Woodstream remain. 

This present Motion addresses the claim of patent infringement directly. Agrizap alleges

that patent claims 1, 2, 3, 5, 10, and 16 of the 636 patent are infringed by Woodstream’s

electronic mouse and rat traps. This Court previously determined the claim constructions for

these patent claims. See Agrizap, Inc. v. Woodstream Corp., 431 F. Supp.2d 518, 525-532 (E.D.

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Pa. 2006) (construing patent claims at issue). Woodstream argues that the Woodstream traps do

not infringe on these claims of the 636 patent either literally or under the doctrine of equivalents. 

Moreover, Woodstream argues that Agrizap is prohibited from claiming infringement under the

doctrine of equivalents because of prosecution history estoppel. In response, Agrizap argues that

these claims have been infringed either literally or under the doctrine of equivalents and its

expert, Dr. Barry N. Feinberg, provides the necessary facts to show that there are genuine issues

of material fact. With respect to prosecution history estoppel, Agrizap argues that it can rebut

the presumption established by that doctrine so that it is not barred from claiming infringement

under the doctrine of equivalents. For the following reasons, Woodstream’s Motion for Partial

Summary Judgement is denied as to literal infringement and granted as to infringement under the

doctrine of equivalents. 

II. SUMMARY JUDGMENT STANDARD

“Summary judgment is appropriate when, after considering the evidence in the light most

favorable to the nonmoving party, no genuine issue of material fact remains in dispute and ‘the

moving party is entitled to judgment as a matter of law.’” Hines v. Consol. Rail Corp., 926 F.2d

262, 267 (3d Cir. 1991)(citations omitted). The inquiry is “whether the evidence presents a

sufficient disagreement to require submission to the jury or whether it is so one-sided that one

party must prevail as a matter of law.” Anderson v. Liberty Lobby, Inc., 477 U.S. 242, 251-52

(1986). The moving party carries the initial burden of demonstrating the absence of any genuine

issues of material fact. Big Apple BMW, Inc. v. BMW of N. Am. Inc., 974 F.2d 1358, 1362 (3d

Cir. 1992). “A fact is material if it could affect the outcome of the suit after applying the

substantive law. Further, a dispute over a material fact must be ‘genuine,’ i.e., the evidence must

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be such ‘that a reasonable jury could return a verdict in favor of the non-moving party.’”

Compton v. Nat’l League of Prof’l Baseball Clubs, 995 F. Supp. 554, 561 n.14 (E.D. Pa. 1998),

aff’d, 172 F.3d 40 (3d Cir. 1998)(citations omitted). Once the moving party has produced

evidence in support of summary judgment, the non-moving party must go beyond the allegations

set forth in its pleadings and counter with evidence that demonstrates that there is a genuine issue

of fact for trial. See Big Apple BMW, at 1362-63. Summary judgment must be granted “against

a party who fails to make a showing sufficient to establish the existence of an element essential

to that party’s case, and on which that party will bear the burden of proof at trial.” Celotex Corp.

v. Catrett, 477 U.S. 317, 322 (1986). A district court should approach a summary judgment

motion on the factual issue of infringement with great care. Amhil Enterprises Ltd. v. Wawa,

Inc., 81 F.3d 1554, 1557 (Fed. Cir. 1996). “Summary judgment may, however, properly be

decided as a matter of law when no genuine issue of material fact exists and no expert testimony

is required to explain the nature of the patented invention or the accused product or to assist in

their comparison.” Id. at 1557-58.

III. DISCUSSION

A. Literal Infringement

Woodstream argues that its electronic rat and mouse traps do not literally infringe on

Claims 1, 2, 3, 5, 10, and 16 of the 636 patent. Woodstream offered the Declaration and expert

report of Dr. Charles A. Eldering to show that there is no infringement because several of the

claim limitations in the 636 patent are not found in the Woodstream traps. In response, Agrizap

submitted the Declaration and rebuttal expert report of Dr. Barry N. Feinberg, P.E. Woodstream

contends that none of the evidence presented by Agrizap is inconsistent with Dr. Eldering’s

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description of the Woodstream traps. Thus, according to Woodstream, there are no genuine

issues of material fact as to the structure, function, and operation of the Woodstream traps and

summary judgment of patent noninfringement should be granted. Conversely, Agrizap argues

that there are genuine issues of material fact because Dr. Feinberg interprets the Woodstream

traps differently than Dr. Eldering and finds that there is literal infringement of the 636 patent. 

For the following reasons, this Court has determined that there are genuine issues of material fact

as to the literal infringement of the 636 patent.

Determining infringement is a two-step process where this Court must first construe the

asserted claims and then compare the properly construed claims to the allegedly infringing

devices. Pause Tech. LLC v. TIVO Inc., 419 F.3d 1326, 1335 (Fed. Cir. 2005). This Court

completed the first step of this process, the claim construction, in a previous decision. See

Agrizap, 431 F. Supp.2d at 525-532. With respect to the second step, “[t]he patentee must show

that the accused device meets each claim limitation either literally or under the doctrine of

equivalents.” Pause Tech, 419 F.3d at 1335. 

“Literal infringement is found where the accused device falls within the scope of the

asserted claims as properly interpreted.” Lantech, Inc. v. Keip Mach. Co., 32 F.3d 542, 547 (Fed.

Cir. 1994). Each limitation of the asserted claim must be met by the accused device exactly. Id. 

If even one claim limitation within the asserted claim is missing or not met, there is no literal

infringement. MicroStrategy Inc. v. Business Objects, S.A., 429 F.3d 1344, 1352 (Fed. Cir.

2005). Literal infringement is a question of fact. Biagro Western Sales, Inc. v. Grow More, Inc.,

423 F.3d 1296, 1301 (Fed. Cir. 2005). It is important to note that “[t]here are no broad rules,

naturally enough, because of the intensely factual nature of the inquiry.” Robert L. Harmon,

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Patents and the Federal Circuit, § 7.2(a)(ii) (7th ed. 2005). 

1. Claim 1(b)

The first patent claim at issue is Claim 1(b). Claim 1(b) states: “triggering the activation

of a high voltage and current generator in response to said sensed presence, said generator

coupled between said high voltage electrode and said reference electrode, said triggered

generator being activated for a predetermined time period.” The two terms in this claim that are

at issue are “triggering” and “predetermined time period.”

This Court construed “triggering” as: “the sensed presence of a pest results in an

immediate and irreversible triggering of the high voltage and current generator.” Agrizap, 431 F.

Supp.2d at 526. Woodstream argues that the activation of the high voltage and current generator

in the Woodstream traps is not immediate and irreversible. In his expert report and in his

Declaration, Dr. Eldering explains how the Woodstream traps are based on the use of a

microprocessor that runs software to accomplish all of its functions. (Eldering Report ¶ 45;

Eldering Decl. ¶ 10). He explains how the Woodstream traps go through a series of tests to

verify the presence of a pest before triggering the generator:

The microprocessor wakes up from a sleep state due to an interrupt generated by

the detection of a pest as sensed on PORT6 (pin 10) and enters the “WAKEUP”

portion of the code. The subsequent section of code, labeled “MOUSHV”,

contains a conditional skip operation, “JBS PORT6, MOUSEIN”, which causes

the subsequent line of code “JMP MYSEP” to be skipped if there is a pest present

as detected on pin 10 as determined by a PORT6(MOUSEIN) = 1 test. If a pest is

not present, the “JMP MYSEP” code causes the microprocessor to return to the

MYSEP portion of the code, resulting in re-entry into a sleep state. It should be

noted that there are two JBS PORT6, MOUSEIN tests in the code. These tests

prevent the sensed presence of the pest from causing an immediate and

irreversible triggering of the high voltage and current generator due to the fact that

the code will cause the microprocessor to return to a sleep state in the event that

the pest is not detected three times on pin 10, the first detection causing the

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microprocessor to wake up, and the second two detections allowing the

microprocessor to continue on to activate the high voltage rather than returning to

a sleep state. It is my opinion that receipt of an interrupt to wake up the

microprocessor and the subsequent tests to confirm the presence of a pest are not

an immediate and irreversible triggering of the high voltage and current generator.

(Id.). More succinctly, in his expert report, he states that “the process of having a

microprocessor wake up due to the suspected presence of a pest and perform several (in this case

two) tests to confirm the presence of a pest is not the same or analogous to the triggering

described in” Claim 1(b). (Eldering Report ¶ 45). These tests to ensure the presence of a pest

before activating the generator show, in his opinion, that the triggering of a Woodstream trap is

not immediate. In addition, Dr. Eldering believes that the triggering is not irreversible because if

one of the test fails, the microprocessor goes back into sleep mode.

In response, Agrizap argues that Woodstream is mischaracterizing the sensing and

verification process (the tests explained above) within the Woodstream traps. According to

Agrizap, the pest is not truly sensed in the Woodstream traps until the verification process is

complete. Dr. Feinberg, Agrizap’s expert, states that “[o]nce the Woodstream traps sense that

the rodent is really between the high voltage electrodes, it initiates the turning on of the high

voltage generator to kill the rodent.” (Feinberg Decl. ¶ 4). He points out that Dr. Eldering’s

description even establishes that the sensed presence of a pest does not occur until after the

verification tests have been successful. Dr. Eldering’s description states that “[i]f, due to the

waking up and subsequent two tests for the presence of the pest it is determined that there is a

pest present, the program continues on to activate the high voltage generator.” (Eldering Report

¶ 45). Thus, according to Agrizap, sensing does not occur until after this verification process is

completed and then the triggering to activate the generator occurs immediately and irreversibly

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after this sensed presence is established. 

This disagreement between the experts shows that there is a factual dispute over when the

Woodstream traps officially establish a “sensed presence” of a pest; before, during, or after the

verification process is complete. Because “triggering” is not determined until the sensed

presence of a pest has occurred, this factual dispute effects when “triggering” actually occurs in

these traps and thus whether it is “immediate” and whether it is “irreversible.” The testimony of

experts seems necessary to resolve this dispute. See Amhil, 81 F.3d at 1557 (stating that

summary judgment is only proper for infringement cases when there is no genuine issue of

material fact and no expert testimony is required). There are technical and factual aspects

concerning the verification tests within the Woodstream traps that need to be examined and

resolved by the trier of fact.

This Court construed “predetermined time period” as: “the time period between

activation and deactivation of the generator that has its length programmed prior to the triggering

of the generator.” Agrizap, 431 F. Supp.2d at 527. Woodstream argues that the amount of time

the high voltage generator is activated in the Woodstream traps depends upon conditions that

cannot be predetermined. According to Woodstream, the activation time period can only be

determined after the fact “because it depends upon whether the trap detects a kill after one, two,

or three activations, or whether no kill is detected after three attempts.” (Woodstream Partial

Summ. J. Mem. 12). Dr. Eldering states that “the Woodstream products can have up to three

cycles of high voltage before the unit needs to be reset. Claim 1 of the ‘636 patent calls for

activation of the generator for a predetermined time period, whereas the Woodstream products

perform three high voltage cycles.” (Eldering Report ¶ 46). Dr. Eldering further explains:

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the Woodstream traps can perform up to three activations depending on if and

when the pest leaves the unit. Therefore, the time period between the initial

activation and final deactivation (requiring a manual reset) is dependent on

external timing parameters (e.g. presence of the pest) and is not a definitive time

period. As a result, the total time between activation and the deactivation

requiring a manual reset cannot be predetermined.

(Eldering Decl. App. A). Thus, Woodstream argues that the time period between activation and

deactivation fluctuates because the Woodstream trap may run only one cycle, two cycles, or three

cycles depending on external factors such as the presence of a pest in the trap. 

In response, Dr. Feinberg declares that the triggered generator in a Woodstream trap is

activated for a predetermined time period. He cites to Dr. Eldering’s admission to such in the

claim chart attached to his Declaration. Dr. Eldering states that “[t]he Woodstream traps utilize

functions in the microprocessor to establish a predetermined time period for an individual

activation cycle of the generator, the length of which is programmed prior to the triggering.” 

(Id.). In addition, Dr. Eldering provides a state diagram and state tables of the Woodstream traps

in Appendix D.2 and D.3, respectively, of his expert report that indicate that the traps have a

predetermined time period. The diagram in Appendix D.2 “shows that the high voltage in the rat

and mouse traps is turned on, activated, for a fixed period of time shown as )T. Then . . .

[Appendix] D.3 . . . [shows] that the high voltage output is activated for 20 seconds for the

mouse trap and 120 seconds for the rat trap.” (Feinberg Decl. ¶ 6); see also (Feinberg Rebuttal

Report 3-4). Therefore, Dr. Feinberg concludes that:

it is clear that the Woodstream [traps] contain this element of claim 1. It is

irrelevant that the Woodstream devices can trigger the generator multiple times. 

This element of claim 1 does not address how many times the high voltage

generator is activated, only that when the high voltage generator is triggered that

it is activated for a predetermined time period.

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(Feinberg Decl. ¶ 6). According to Agrizap, the 20 second time period for the mouse trap and the

120 second time period for the rat trap are the predetermined time periods between activation and

deactivation of the high voltage generator that are programmed prior to triggering. 

 Therefore, a genuine issue of material fact exists concerning whether the high voltage

generator in the Woodstream traps is activated for a predetermined time period programmed

prior to triggering or not. Woodstream claims there is not a predetermined time period because

the time period between initial activation and final deactivation depends on external factors such

as the presence of the pest. Thus, the length of time is variable depending on if the pest is killed

after the first, second, or third cycle, or not killed at all because the pest left the trap. Agrizap, on

the other hand, claims that there is a time period between activation and deactivation

programmed prior to triggering. This is evidenced, according to Agrizap, by the 20 second and

120 second time periods mentioned in Eldering’s expert report. In addition, Agrizap believes

that Woodstream is obscuring this fact by discussing its verification process and looking at the

time period between initial activation and final activation instead of just between a single

activation and deactivation of the generator. It is important to note that the claim construction

discusses “the time period between activation and deactivation” and is referring to the time

between these two exact events. Thus, the fact finder will have to determine when a single

activation and its deactivation occurs within the Woodstream traps; how the verification tests

interplay with activation and deactivation; and if the length of time between activation and

deactivation is “programmed prior to the triggering of the generator.” The evidence offered by

both parties indicate that there are factual disputes as to whether the Woodstream traps are

activated for a “predetermined time period.”

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2. Claim 1(d)

The second patent claim at issue is Claim 1(d). Claim 1(d) states: “deactivating said

generator only upon expiration of said predetermined time period or in response to a reset

signal.” The terms in contention within this claim are “deactivating” and “reset signal.”

This Court construed “deactivating” as: 

the stopping of the activated generator either upon the expiration of the

predetermined time period or in response to a reset signal. The activated generator

can be deactivated only upon either of these two conditions (expiration of

predetermined time period or in response to a reset signal) and the generator must

be capable of being deactivated by both of these conditions.

Agrizap, 431 F. Supp.2d at 527. “Reset signal” is construed as: “the power on reset signal.” Id.

at 528. Woodstream argues that deactivation in the Woodstream traps is different than in the 636

patent because the generator does not deactivate in response to a power on reset signal. Thus,

both conditions are not satisfied in the Woodstream traps. Dr. Eldering states that:

[i]f the power is off in the Woodstream traps, the high voltage generator is off and

inherently deactivated. In the Woodstream traps, the generator can be inherently

deactivated in response to a power down, but this power down does not result in a

reset (power on reset) signal. The Woodstream traps have a reset pin which is

pulled to a logic high state upon power-up, with a power on reset signal only

occurring during powering up of the circuit from its off condition. Any

“resetting” that occurs to the microprocessor as a result of a power up causes entry

into a main portion of the code. Thereafter, the pin remains in a logic high state

and is certainly not used when the generator is running. Therefore, the activated

generator cannot be deactivated in response to a reset signal.

(Eldering Decl. ¶ 11). Woodstream is essentially arguing that the activated generator in the

Woodstream traps will deactivate when the power is turned off, but does not deactivate in

response to any power on reset signal because the power on reset signal occurs only upon the

powering up of the circuit. Accordingly, Woodstream states that “[b]y its very definition, the

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power on reset signal is generated on power up when the circuit is already in an off condition. A

circuit cannot be in an off condition and also be in an activated or running condition.” 

(Woodstream’s Reply Mem. 7). Thus, a Woodstream trap cannot be deactivated by a power on

reset signal because that signal only functions when the trap is already deactivated and turned off.

While Woodstream states that its traps do not deactivate in response to a reset signal,

Agrizap argues that the Woodstream traps do perform this function. Dr. Feinberg finds that:

on “power up” the Woodstream devices . . . go to the “MAIN” trap setup

subroutine, then branching to MYSEP subroutine to wait for the detection of the

rodent. This operation is identical to the “RESET” operation as noted in the state

tables [in Dr. Eldering’s expert report]. This indicates that the program operation

“MAIN” is, in reality, the power on “RESET” operation. Further, [in] appendix

D.4 - Commented Code for Mouse Killer it is clearly seen that the subroutine

“RESET” upon “power on” branches to the subroutine “MAIN” where it turns off

the high voltage switch.

(Feinberg Decl. ¶ 7). Woodstream does not really dispute Dr. Feinberg’s description, but rather

argues that he is only addressing what occurs upon powering up the trap after it was already

turned off and deactivated. According to Woodstream, there is no indication from Dr. Feinberg’s

description that the MAIN subroutine, which Dr. Feinberg suggests is the power on reset signal,

“would ever take place during the high voltage generation so as to deactivate the generator,” 

(Woodstream’s Reply Mem. 7), but rather, it would only take place after deactivation has already

occurred. 

The factual dispute at issue here is whether deactivation of the Woodstream traps can

occur in response to a power on reset signal. Woodstream is interpreting the power on reset

signal to be the powering up of the trap and thus does not involve powering down, or

deactivating the trap. Agrizap seems to view the power on reset signal as an “on and off” button. 

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The finder of fact will have to determine what truly is the function of the power on reset signal

and whether the Woodstream traps also literally perform this function. Expert testimony will

likely be required to understand the technical workings of the power on reset signal. See Amhil,

81 F.3d at 1557 (stating that summary judgment is only proper for infringement cases when there

is no genuine issue of material fact and no expert testimony is required). Based on the evidence

provided by both parties, this factual issue is in dispute.

3. Claim 1(e)

The third patent claim at issue is Claim 1(e). Claim 1(e) states: “inhibiting said triggering

step once activation of said generator is triggered, until said reset signal is detected.” The

“inhibiting” term within this claim is at issue. This Court construed “inhibiting” as: “the

triggering step is inhibited upon each and every activation of the triggering of the generator until

the power on reset signal is detected; each time the high voltage generator is activated, further

triggering cannot take place, at least until the power on reset signal is detected.” Agrizap, 431 F.

Supp.2d at 529.

Woodstream contends that its traps do not inhibit triggering upon each and every

activation of the generator until the power on reset signal is detected. Instead, the traps allow up

to three automatic activations of the generator without any need of a power on reset signal to deinhibit the traps’ triggering step. Dr. Eldering explains that triggering is not inhibited after each

and every activation of the generator because “after each of the first two activations, the trap is

re-armed without requiring a power on reset signal. The Woodstream traps enable up to three

automatic activations of the generator. After the third activation of the generator, the system

enters sleep mode.” (Eldering Decl. ¶ 12). Thus, according to Woodstream, there is not an

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inhibition of the triggering after each and every activation of the generator because its traps

consecutively go through three activations without requiring a reset after each activation.

In response, Agrizap argues that Woodstream is improperly relying on how its system

works when it fails to kill the pest. Agrizap does not dispute that the Woodstream traps apply

three high voltage cycles. Agrizap, however, argues that Woodstream admits that “[i]f, after any

of the three high voltage cycles, it is determined that a pest has been killed, then the unit will be

disarmed and must be reset.” (Woodstream’s Statement of Material Facts Not in Genuine

Dispute ¶ 7). Dr. Feinberg explains how the triggering is inhibited after each cycle of activation

until the reset signal is detected. He states that when the Woodstream traps are turned on, the

computer program goes though an initial step, MAIN, and then goes to a subroutine MYSEP to

wait for detection of the pest. (Feinberg Decl. ¶ 7). Dr. Feinberg states that the MYSEP

subroutine represents the “power on reset signal” in the Woodstream traps and that “[t]he

triggering of the high voltage is inhibited until the execution of the MYSEP subroutine has been

accomplished.” (Id.). He acknowledges that the Woodstream traps are capable of three

activations of the high voltage, but explains that:

[a]fter each of the first two activations, the Woodstream traps are reset by

branching in their computer program to the subroutine MYSEP which in turn

generates the identical sequence of steps used as the power on reset signal in the

Woodstream rat and mouse traps. Thus the “reset signal” produced by the

MYSEP subroutine is the signal that is generated upon the powering up of the

circuit from its off condition as construed by the Court.

(Id.). Accordingly, Agrizap states that the Woodstream traps are inhibited after each activation

of the generator and require reset by way of the MYSEP subroutine before the traps can be retriggered.

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Therefore, a genuine factual dispute exists between the parties. As shown above,

Woodstream claims that because its traps go through up to three activations before entering a

sleep mode, triggering is not inhibited after each and every activation. Agrizap, on the other

hand, argues that after each of the activations, the Woodstream traps are inhibited and require a

reset signal through the process of the MYSEP subroutine before re-triggering can occur. Thus,

whether the Woodstream traps infringe Claim 1(e) is a genuine issue of material fact.

4. Claims 2, 3, 5, and 10

Patent claims 2, 3, 5, and 10 of the 636 patent are dependent claims. These claims are

dependent on independent Claim 1. Patent claims can be written in independent, dependent, or

multiple dependent form. Herbert F. Schwartz, Patent Law and Practice, § 2.III.B.1 (3d ed.

2001); 35 U.S.C. § 112, ¶ 3. An independent claim is completely self-contained. Schwartz,

supra, at § 2.III.B.1. On the other hand, a dependent claim contains a reference to a previous

claim and then specifies a further limitation of the subject matter claimed. Id.; 35 U.S.C. § 112, ¶

3. A dependent claim is “construed to incorporate by reference all the limitations of the claim to

which it refers.” Id. It is a fundamental principle of patent law that “dependent claims cannot be

found infringed unless the claims from which they depend have been found to have been

infringed.” Jeneric/ Pentron, Inc. v. Dillon Company, Inc., 205 F.3d 1377, 1383 (Fed. Cir. 2000). 

Woodstream argues that only the independent claims, Claim 1 and Claim 16, require

consideration by this Court because if these claims are not infringed then dependent Claims 2, 3,

5, and 10 are not infringed. Agrizap argues that Woodstream does not meet its summary

judgment burden of establishing the absence of any triable issues of material fact because it is

silent on Agrizap’s claims that the Woodstream traps infringe dependent Claims 2, 3, 5, and 10. 

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Furthermore, Agrizap argues that Dr. Eldering does not dispute Dr. Feinberg’s conclusions of

infringement with respect to these claims. 

Because the claim limitations within Claim 1 are incorporated by reference in Claims 2,

3, 5, and 10, then the factual disputes over the Claim 1 claim limitations are also factual disputes

for these dependent claims. In addition, factual issues as to the specific limitations within Claims

2, 3, 5, and 10 were not addressed by the moving party, Woodstream. Therefore, summary

judgment is inappropriate on these claims.

5. Claim 16

The last patent claim at issue is Claim 16. This Court has previously construed

subparagraphs (b)(i), (b)(iii), and (b)(iv) of Claim 16. Agrizap, 431 F. Supp.2d at 531-32.

Woodstream argues that there is no literal infringement of Claim 16 because Agrizap is trying to

correlate the specific electronic structural components laid out in Claim 16 to the computer code

instructions performed by the Woodstream microprocessor. In sum, Woodstream contends that

computer code is not the circuitry of the specific electronic structural components recited in

Claim 16, so there can be no literal infringement. Agrizap argues that Dr. Feinberg establishes

that the Woodstream traps literally infringe Claim 16. Given that there is disagreement between

the experts, a genuine factual dispute exists and summary judgment is inappropriate.

a. Claim 16(b)(i)

Subparagraph (b)(i) of Claim 16 reads:

b) an electronic portion comprising:

i) a resistive switch coupled between said high voltage electrode and said

reference electrode, said resistive switch further comprising a trigger circuit

having a trigger output and an arm/ disarm input.

 

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This Court construed Claim 16(b)(i) as “a switch that is physically connected across the

electrodes. The switch includes a distinct trigger circuit with a trigger output and an arm/ disarm

input.” Agrizap, 431 F. Supp.2d at 531.

Woodstream argues that its traps do not have a resistive switch which includes a trigger

circuit and an arm/ disarm input, but rather have a microprocessor that accomplishes the

activation of the high voltage generator. (Eldering Decl. ¶ 13; Eldering Report ¶ 55). Dr.

Eldering states that:

[t]he Woodstream products do not have a trigger circuit, but rather use the

microprocessor to accomplish the activation of the high voltage circuit. 

Furthermore, the trigger circuit of claim 16 includes a trigger output and an arm/

disarm input. The microprocessor of the Woodstream products does not have a

structure that resembles the trigger circuit of claim 16, nor does it have an arm/

disarm input. While awaiting a pest, the microprocessor . . . enters into sleep

mode, awakens upon the detection of the presence of a pest, . . .checks for the

presence of a pest several times before activating the high voltage generator. The

microprocessor cannot, in my opinion, be considered to be a trigger circuit as

described in claim 16.

(Id.). Dr. Eldering states that the microprocessor is the operative mechanism within the

Woodstream traps and cannot be viewed as the structural component of a resistive switch

containing a triggering circuit with a trigger output and an arm/ disarm input.

Agrizap addresses each portion of the claim construction of Claim 16(b)(i) and shows

how each is literally present in the Woodstream traps. First, Dr. Feinberg show that the

Woodstream traps have “a switch that is physically connected across the electrodes.” He

references Dr. Eldering’s Declaration which states that “[t]he Woodstream traps utilize a

microprocessor (EM78P153) to detect the presence of a pest as sensed by a voltage divider

circuit connected to pin 10 (utilized in the microprocessor as “PORT6") of the microprocessor.”

Case 2:04-cv-03925-RK Document 102 Filed 10/19/06 Page 17 of 33
1 Dr. Feinberg added an additional sentence, “The switch includes a distinct trigger circuit with a

trigger output and an arm/ disarm input,” to his quote of Dr. Eldering that is not actually present in Dr. Eldering’s

Declaration. This Court disregarded this sentence in its consideration of the present summary judgment motion.

18

(Feinberg Decl. ¶ 9 (citing Eldering Decl. ¶ 10))1. This “voltage divider circuit” is the switch

physically connected across the electrodes in the Woodstream traps. For further support, Dr.

Feinberg also states that “the electronic schematics of the Woodstream traps [show] the voltage

divider network . . . as part of the high voltage electrode system of the Woodstream traps.”

(Feinberg Decl. ¶ 9). Second, Dr. Feinberg contends that the Woodstream traps have a “distinct

trigger circuit with a trigger output.” He states that:

[t]he Woodstream traps utilize[] assembly language code that causes the

microprocessor to respond (wake up) if there is an appropriate change in

resistance across the electrodes indicat[ing] the presence of a rodent. This change

in resistance causes a voltage to be applied to pin 10 of the microprocessor. This

sets into motion the “triggering” of the high voltage as this term has been

construed by the Court. Thus, the Woodstream traps have a “trigger circuit”

which have trigger outputs, i.e. an output that sets into motion the release of the

high voltage used to kill the rodent in the trap. This circuit that senses the change

in resistance resulting in a voltage input to pin 10 of the microprocessor is a

distinct trigger circuit whose output is used to trigger the high voltage output of

the Woodstream traps.

(Id.). Third, Dr. Feinberg explains that the Woodstream traps have an “arm/ disarm input” in its

trigger circuit. He states that the Woodstream trap:

is armed when it received a reset signal. The Woodstream rat and mouse traps

perform the same function in the assembler computer code in the microprocessor

that makes up part of the electronics in these devices. When a rodent is detected

the Woodstream traps disable the interrupts to the microprocessor with the

instruction (DISI). Then, in the sequence of computer instructions it branches to

the subroutine KMOUSE to kill the rodent with high voltage electrical current. . . . 

[T]he subroutine KMOUSE, contains a set of three assembler code computer

instructions that first turns on the high voltage switch (BS PORT6, PLUSE), then

institutes a delay in terminating the high voltage (CALL DELY76) in order to

deliver the high voltage to the rodent for the specified time. Finally, the high

voltage switch is turned off, with the instruction (BC PORT6, PLUSE). When

Case 2:04-cv-03925-RK Document 102 Filed 10/19/06 Page 18 of 33
19

these assembler code instructions are executed in the microprocessor used in the

Woodstream traps, the triggering step of the high voltage is inhibited. Therefore,

the Woodstream rat and mouse trap[] stops, deactivates, the activated high voltage

generator upon the expiration of the predetermined time period. Once the high

voltage is terminated, the microprocessor instruction set goes back to arming the

system again.

(Id.). Thus, Dr. Feinberg explains how the subroutines of the microprocessor turn on and arm the

triggering circuit, then disarm it, and then when the voltage is terminated, arm the system again.

Dr. Feinberg’s analysis creates genuine factual disputes as to whether the Woodstream

traps have “a switch that is physically connected across the electrodes” and whether they have a

“trigger circuit having a trigger output and an arm/ disarm input.” While Dr. Feinberg does

discuss how these functions are present in the Woodstream traps within the microprocessor, he

makes a reasonable argument that the microprocessor and its underlying computer code literally

perform the functions in question. At summary judgment, it is not the job of this Court to weigh

the evidence presented, but rather just to determine if there any genuine issues of material fact. 

See Ritchie v. Henderson, 161 F. Supp.2d 437, 446 (E.D. Pa. 2001) (citing Anderson v. Liberty

Lobby, Inc., 477 U.S. 242, 255 (1986)). All that is necessary to show that a dispute over a

material fact is “genuine,” is for the evidence to be such ‘that a reasonable jury could return a

verdict in favor of the non-moving party.’” Compton, 995 F. Supp. At 561 n.14. The evidence

Agrizap presents meets this standard. It will be up to the fact finder to determine if the computer

code processes described by Dr. Feinberg literally infringe the elements described in Claim

16(b)(i).

b. Claim 16(b)(iii)

Subparagraph (b)(iii) of Claim 16 states:

Case 2:04-cv-03925-RK Document 102 Filed 10/19/06 Page 19 of 33
20

b) an electronic portion comprising:

iii) a timing module having an input coupled to said trigger output of said resistive

switch, a control output coupled to said generator control input and an arm/ disarm output

coupled to said arm/ disarm input of said resistive switch.

This Court construed this subparagraph as: “a specific distinct timing module having an input

and two outputs. The input is connected to the trigger output of the resistive switch. A control

output is connected to the high voltage generator control input. An arm/ disarm output is

connected to the arm/ disarm input of the resistive switch.” Agrizap, 431 F. Supp.2d at 531. 

Woodstream argues that its traps do not have a timing module, but rather “use the

microprocessor to initiate generation of the high voltage.” (Eldering Report ¶ 56). Dr. Eldering

states that:

the Woodstream traps use several portions of computer code to generate pulses,

those pulses being used as the basis for the generation of high voltage and current. 

Control of the timing of the pulses originates from the various sections of the

computer code, which cannot, in my opinion, be considered to be a specific

distinct timing module.

(Eldering Decl. ¶ 15). On the other hand, Agrizap argues that there is a distinct timing module in

the Woodstream traps. Dr. Feinberg states that “[w]hen there is a sensed input to the

microprocessor, the program branches to a timing subroutine.” (Feinberg Rebuttal Report, 13). 

More specifically, “[w]hen a rodent is present in the resistive switch, the resistive switch

produces a voltage output that is applied to pin 10 of the microprocessor. Through a sequence of

programming steps, the computer program branches to a timing subroutine module, DELY760.” 

(Feinberg Decl. ¶ 12). This timing subroutine module, DELY760, is a specific distinct timing

module “whose input is ‘connected’ via programming steps to the resistive switch.” (Id.). Dr.

Feinberg also explains how the requisite input and outputs of Claim 16 (b)(iii) are present. (Id.,

Case 2:04-cv-03925-RK Document 102 Filed 10/19/06 Page 20 of 33
21

at ¶ 13, 14).

Similar to subparagraph (b)(i), Dr. Feinberg’s analysis creates a factual dispute over

subparagraph (b)(iii). Both parties raise opposing viewpoints and facts as to whether the

Woodstream traps have a timing module with an input and two outputs connected to the resistive

switch. The strength of either sides factual arguments, as stated above, is not for this Court to

decide at summary judgment.

c. Claim 16(b)(iv)

Lastly, the last clause of Claim 16(b)(iv) is at issue. It reads: “said timing module

disarms said trigger circuit of said resistive switch upon said activation of said timer module until

said timer module is reset.” This Court construed this clause as: “the timing module has an

output that is coupled to the trigger circuit of the resistive switch to disarm the trigger circuit

until a power on reset signal re-enables or re-sets the timing module.” Agrizap, 431 F. Supp.2d

at 531-32.

Dr. Eldering contends, as he explained with regards to Claim 16 (b)(i) and (b)(iii), that

the microprocessor in its traps do not have a timing module and an arming and disarming of a

resistive switch. (Eldering Report ¶ 57; Eldering Decl. ¶ 16). Dr. Feinberg states that the

Woodstream traps “perform the same function [as described by this portion of Claim 16(b)(iv)]

by executing assembler computer code subroutines in the microprocessor that makes up part of

the electronics in these devices.” (Feinberg Decl., ¶ 16). Dr. Feinberg then goes through a

lengthy discussion of how a sequence of computer code instructions in the microprocessor

literally perform the function of disarming the trigger circuit until a power on reset signal resets

the timing module. (Id.). 

Case 2:04-cv-03925-RK Document 102 Filed 10/19/06 Page 21 of 33
22

Once again, the issue is whether the processes of the microprocessor in the Woodstream

traps literally infringe the claim in question. The Woodstream traps literally infringe the 636

patent if they fall within the scope of the asserted claims as properly interpreted and each claim

limitation is met exactly. Lantech, 32 F.3d at 547. Any deviation precludes a finding of

infringement. Id. Agrizap, through Dr. Feinberg, makes reasonable arguments based on

evidence from his understanding of the workings of the Woodstream traps. Whether the fact that

these processes are accomplished by a microprocessor falls within the scope of Claim 16 is a

question for the finder of fact to decide. 

B. Doctrine of Equivalents

If there is no literal infringement, Agrizap argues that it can still show that the

Woodstream traps infringe the 636 patent under the doctrine of equivalents. Woodstream argues

that Agrizap cannot utilize the doctrine of equivalents because it is prohibited from doing so

pursuant to the prosecution history estoppel doctrine. This Court finds that prosecution history

estoppel applies and Agrizap is prohibited from asserting infringement under the doctrine of

equivalents.

“The scope of a patent is not limited to its literal terms but instead embraces all

equivalents to the claims described.” Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co.,

Ltd., 535 U.S. 722, 732 (2002). Thus, an accused device that does not literally infringe a patent

claim may still infringe that claim under the doctrine of equivalents if every element in the claim

is either literally or equivalently present in the accused device. Sage Products, Inc. v. Devon

Industries, Inc., 126 F.3d 1420, 1423 (Fed. Cir. 1997). A claim element is equivalently present

“if only ‘insubstantial differences’ distinguish the missing claim element from the corresponding

Case 2:04-cv-03925-RK Document 102 Filed 10/19/06 Page 22 of 33
23

aspects of the accused device.” Id. Stated another way, the doctrine of equivalents applies if the

accused device “performs substantially the same function in substantially the same way to obtain

the same result.” Graver Tank & Mfg. Co., Inc. v. Linde Air Products Co., 339 U.S. 605, 608

(1950). Equivalence is a question of fact and summary judgment should be granted where no

reasonable fact finder could find equivalence. Sage Products, 126 F.3d at 1423. 

The doctrine of prosecution history estoppel may bar a patentee from asserting the

doctrine of equivalents. Honeywell Int’l Inc. v. Hamilton Sundstrand Corp., 370 F.3d 1131,

1139 (Fed. Cir. 2004). To determine prosecution history estoppel, the Court must examine any

relevant amendments to the patent made by the patentee during its prosecution before the Patent

and Trademark Office (“PTO”). Prosecution history estoppel may occur when a narrowing

amendment to a patent claim is made to satisfy any requirement of the Patent Act. Business

Objects, S.A. v. Microstrategy, Inc., 393 F.3d 1366, 1374 (Fed. Cir. 2005). This narrowing

amendment gives rise to a presumption that the patentee surrendered any subject matter between

the original claim and the amended claim. Id. Thus, the patentee surrenders any equivalent

within the scope of the original claim and the amended claim. “[A] narrowing amendment may

occur when either (1) a preexisting claim limitation is narrowed by amendment or (2) a new

claim limitation is added by amendment.” Honeywell, 370 F.3d at 1140. The patentee, however,

may overcome this presumption by showing “that the alleged equivalent could not reasonably

have been described at the time the amendment was made, or that the alleged equivalent was

tangential to the purpose of the amendment, or that the equivalent was not foreseeable (and thus

not claimable) at the time of the amendment.” Business Objects, 393 F.3d at 1374. The patentee

bears the burden of proving that an amendment was not made for a reason that would give rise to

Case 2:04-cv-03925-RK Document 102 Filed 10/19/06 Page 23 of 33
24

estoppel and if estoppel does apply, the patentee also bears the burden of showing that the

amendment does not surrender the particular equivalent in question. Festo, 535 U.S. at 740. 

Prosecution history estoppel and all issues relating to its application and scope are questions of

law. BiagroWestern Sales, 423 F.3d at 1301-02. 

Therefore, this Court must decide as a matter of law if prosecution history estoppel

prohibits Agrizap from claiming infringement under the doctrine of equivalents. Agrizap states

that during the prosecution of the 636 patent, Claims 1 and 16 were amended such that “the

presumption would likely arise that Agrizap surrendered the subject matter between the original

claim and the amended claim.” (Agrizap’s Resp. to Court’s Letter, 1). Thus, Agrizap does not

challenge that its amendments to the 636 patent give rise to estoppel; however, Agrizap does

argue that it can overcome the presumption it establishes. 

As stated above, there are three possible circumstances in which the patentee can

overcome the presumption. Agrizap relies on the “tangential relationship” circumstance that

asserts that “the rationale underlying the amendment may bear no more than a tangential relation

to the equivalent in question.” Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., Ltd., 344

F.3d 1359, 1369 (Fed. Cir. 2003). The primary consideration in determining this circumstance is 

“whether the reason for the narrowing amendment was peripheral, or not directly relevant, to the

alleged equivalent.” Id. This Court shall only examine the prosecution history record without

introduction of additional evidence, except, if testimony from those skilled in the art as to the

record’s interpretation is necessary. Id. at 1370. The United States Court of Appeals for the

Federal Circuit has stated that while specific instances of “mere tangentialness” cannot be

anticipated, “an amendment made to avoid prior art that contains the equivalent in question is not

Case 2:04-cv-03925-RK Document 102 Filed 10/19/06 Page 24 of 33
25

tangential.” Id. at 1369. However, it does not follow that equivalents not within the prior art

must be tangential to the amendment. Chimie v. PPG Indus., 402 F.3d 1371, 1383 (Fed. Cir.

2005). 

Agrizap argues that the amendments to Claim 1 and 16 were made to overcome prior art

references that utilized simple electronic components rather than the microprocessor/ software

based system which is the equivalent in question. The prior art references that Agrizap was

trying to avoid through its amendments were the Ford, Madsen, Dye, and Stirewalt patents. 

None of these patents and none of the PTO’s communications were concerning the

microprocessor system in question. Thus, Agrizap is arguing that the purpose of the amendments

was to avoid these prior art references and these references bear no relevance, and are thus

tangential, to the alleged microprocessor-based equivalent.

Woodstream argues that Agrizap’s rebuttal argument is both an oversimplification of the

issue and legally insufficient. According to Woodstream, the issue is not whether the

Woodstream microprocessor is different from the prior art references, but whether the elements

of the Woodstream traps asserted to be equivalents are tangential or peripheral to the purposes

for the narrowing amendments. Woodstream contends that the purposes for the amendments are

directly related to the equivalents in the Woodstream traps. This Court agrees with Woodstream.

1. Claim 1(b)

After receiving a second prior art rejection by the PTO, Agrizap amended Claim 1(b) as

follows (underlining shows the language added and bracketing shows the language deleted):

“triggering the activation of [activating] a high voltage and current generator in response to said

sensed presence, said generator coupled between said high voltage electrode and said reference

Case 2:04-cv-03925-RK Document 102 Filed 10/19/06 Page 25 of 33
26

[ground] electrode, said triggered generator being activated for a predetermined time period [in

response to said sensed presence].” During the patent prosecution, Agrizap argued that the claim

limitation concerning the triggering of the activation of the generator in response to a sensed

presence was added because the prior art references, the Dye and Ford patents, do not perform

this function. In its Remarks section of the Amendment, Agrizap states that “Dye does not sense

the presence of a pest between a high voltage electrode and a reference electrode, but rather

between a separate low voltage sensed electrode and a reference electrode” and that “Dye does

not trigger the activation of its generator in response to the sensed presence, but rather activates

the generator in response to the sensed presence.” (Woodstream Mot. Partial Summ. J. Ex. H, at

000119). With respect to the Ford patent, Agrizap argued, “Ford does not trigger activation of

the generator for a predetermined time in response to a sensed presence, but rather simply

activates the generator whenever the mechanical switch is closed.” (Id., at 000124). Thus, the

purpose of the amendment concerning triggering the activation of the generator in response to a

sensed presence was to distinguish the 636 patent from these prior art references that just simply

activate the generator. The equivalent Agrizap is trying to claim here is that the Woodstream

traps accomplish this triggering of the activation through its microprocessor-based system. 

Therefore, the purpose of the amendment and the equivalent both concern the triggering of the

activation of the generator. 

The other amendment made to Claim 1(b) is that the triggered generator is activated for a

predetermined time period. Agrizap made this amendment to distinguish the 636 patent from the

Dye, Stirewalt, and Ford patents that do not maintain activation of the generator for a

predetermined time period. Agrizap argued that “Dye does not maintain the activation of its

Case 2:04-cv-03925-RK Document 102 Filed 10/19/06 Page 26 of 33
27

generator for a predetermined time period, but rather maintains activation for as long as the

presence is sensed.” (Id., at 000119). Agrizap argued that Stirewalt does not run for a

predetermined time period “because the system . . . does not time anything unless a resistive body

is in contact with the electrodes such that current is flowing through the circuit. Thus, there is no

way to know how long the generator of Stirewalt will remain active.” (Id., at 000120). Agrizap

further explains how the time period in Stirewalt is “impossible to predict” and the fact that the

generator could remain energized is a real hazard. (Id., at 000120-121). Agrizap contends that

the 636 patent eliminates this hazardous condition. (Id.) With respect to Ford, Agrizap argued

that “the time which the generator remains active cannot be predetermined because the generator

will deactivate as soon as the body falls away from the switch.” (Id., at 000124). Thus, the

purpose of the amendment was to show that the 636 patent’s generator is activated for a

predetermined time period opposed to being activated for an undefinable time period as in the

prior art references. Agrizap is claiming that the equivalent in question does perform this

function of activating the generator for a predetermined time period via programmed values in

the microprocessor assembly code instructions. Woodstream, on the other hand, claims that its

traps do not activate for a predetermined time period. Therefore, both the purpose of the

amendment and the equivalent in question relate to whether activation occurs for a predetermined

time period. Accordingly, because the equivalents are directly related to purposes for the

amendments made to Claim 1(b), they cannot be considered tangential. 

2. Claim 1(d)

Agrizap amended Claim 1 by adding subsection (d). Claim 1(d) states, “deactivating said

generator only upon expiration of said predetermined time period or in response to a reset

Case 2:04-cv-03925-RK Document 102 Filed 10/19/06 Page 27 of 33
28

signal.” Agrizap argued that “Dye does not deactivate its generator only upon expiration of the

predetermined time or in response to a reset signal, but rather only in response to a lack of a

sensed pest.” (Id., at 000119). Agrizap also argued that “Ford does not deactivate the generator

only upon expiration of a predetermined time or in response to a reset signal.” (Id., at 000124). 

Agrizap, therefore, added this amendment for the purpose of distinguishing the deactivating

function in the 636 patent from the deactivation function in the prior art references. With respect

to the equivalence in question, Agrizap is arguing that the Woodstream traps do deactivate upon

a predetermined time period or through a reset signal within the microprocessor, while

Woodstream argues otherwise Therefore, the purpose of the amendment and the equivalent in

question both concern the deactivating of the generator and cannot be considered tangential.

3. Claim 1(e)

Agrizap amended Claim 1 by adding subsection (e). Claim 1(e) states, “inhibiting said

triggering step once activation of said generator is triggered, until said reset signal is detected.” 

Agrizap’s purpose for this amendment was to distinguish the 636 patent from the prior art

references that do not inhibit the generator from retriggering once it is activated. Agrizap argues

that “Dye does not inhibit a retriggering of the activation of the generator, once activation has

been triggered, until detection of a reset signal, but rather permits activation any time a presence

is sensed.” (Id., at 000119). When discussing the combination of the Dye, Madsen, and Ford

patents, or the combination of the Dye, Madsen, and Stirewalt patents, Agrizap argues that each

combination has the same shortcoming of not deactivating the generator and not preventing it

from reactivating. (Id., at 000125). According to Agrizap, this shortcoming creates a hazardous

condition and possible injury for an unsuspecting human or pet. (Id.). The 636 patent corrected

Case 2:04-cv-03925-RK Document 102 Filed 10/19/06 Page 28 of 33
29

this shortcoming. With respect to the equivalent in question, Agrizap argues that the

Woodstream traps do the same inhibiting function as described in Claim 1(d) but through the

processes of the microprocessor. Therefore, both the purpose of this amendment and the

equivalent are directly related and cannot be considered tangential.

4. Claim 16

Claim 16 was originally prosecuted before the PTO as Claim 13, but was subsequently renumbered upon amendment. The substance of Claim 16 was amended twice during the 636

patent prosecution. The claim limitations within Claims 16(b)(i), (b)(iii), and (b)(iv), which are

at issue in this infringement case, were all added or amended during the patent prosecution. 

Subsection (b)(i) was amended as follows: “a resistive switch coupled between said high

voltage electrode and said reference electrode, said resistive switch further comprising a trigger

circuit having a trigger output and an arm/ disarm input.” Agrizap argued that “Dye does not

teach a switch means having a trigger output which becomes active if not disarmed; the resistive

switch taught by Dye is always armed.” (Id., at 000120). Thus, this amendment was made for

the purpose of showing that the resistive switch in the 636 patent can be disarmed while it cannot

in the Dye patent. Agrizap is trying to claim an equivalent in the Woodstream traps that has this

arm/ disarm function utilizing assembler code instructions programmed into the microprocessor. 

Therefore, both the purpose for the amendment and the equivalent are directly related to the same

issue.

Subsection (b)(iii) was amended as follows: “a [trigger circuit] timing module having an

input coupled to said trigger output of said resistive switch, a control [and an]output coupled to

said generator control input and an arm/ disarm output coupled to said arm/ disarm input of said

Case 2:04-cv-03925-RK Document 102 Filed 10/19/06 Page 29 of 33
30

resistive switch,” The amendments here concern a timing module and the resistive switch

explained above. With respect to the timing module, Agrizap argued that “Dye does not teach a

timing means or timing module of any kind.” (Id.). Agrizap also argued how “Stirewalt does not

teach a timing means/ timing module which disarms the resistive switch from reactivating the

generator after the initiation of the predetermined time period.” (Id., at 000121). Furthermore,

Agrizap states that “[t]here is no recognition in either Stirewalt or Dye, or any teaching, which

instructs or even suggests to someone of ordinary skill how to implement a timer in the pest

electrocution art to” prevent injury or conserve battery power. (Id., at 000122). The purpose of

this amendment was to distinguish the prior art references that had no timing module with the

636 patent which does have a timing module. With respect to the equivalent in question,

Agrizap claims that the Woodstream traps have a timing module performed through a sequence

of computer programming steps. Therefore, the purpose for the amendment and the equivalent in

question both directly relate to the issue of a timing module and thus cannot be considered

tangential. 

Lastly, the last clause of Claim 16(b)(iv) is at issue. This clause was added in its entirety

after the second prior art rejection by the PTO. This clause reads, “wherein said timing module

disarms said trigger circuit of said resistive switch upon said activation of said timer module until

said timing module is reset.” This amendment concerns the timing module and the resistive

switch functions that were discussed above. Thus, the purpose of this amendment, while not

explicitly stated in the prosecution history record, seems to be similar if not the same as the

previously discussed amendments. Also, Agrizap is once again claiming an equivalent that

essentially does these same timing module and resistive switch functions but through the

Case 2:04-cv-03925-RK Document 102 Filed 10/19/06 Page 30 of 33
31

microprocessor, while Woodstream argues otherwise. Therefore, the purpose for the

amendment and the equivalent in question are directly related and not tangential.

In conclusion, Agrizap cannot rebut the presumption established by prosecution history

estoppel because the purpose of Agrizap’s narrowing amendments bear more than a tangential

relationship to the equivalents in question. Agrizap tried to make its tangential relationship

argument based on its broad discussion that the amendments were made for the purpose of

distinguishing the 636 patent from the prior art references and the prior art references did not

have any relation to a microprocessor based system, which is the equivalent in question. This

broad approach to comparing the purpose of the amendments to the equivalents in question is

inappropriate. The fact that the equivalents are not within the prior art does not automatically

lead to the conclusion that they are tangential to the purpose of the amendment. See Chimie, 402

F.3d at 1383; Honeywell Int’l, Inc. v. Hamilton Sunstrand Corp., No. 99-309, 2006 WL 2346446,

*6 (D. Del. Aug. 14, 2006); Windbrella Products Corp. v. Taylor Made Golf Co., Inc., 414 F.

Supp.2d 305, 318 (S.D.N.Y. 2006). This Court had to examine the precise purpose for each

amendment and not just the generalized purpose that they were made to avoid prior art

references. Likewise, the equivalents within the Woodstream trap needed to be examined in

connection with each relevant amendment, rather than just examining the character of the

Woodstream trap as a whole; i.e. the fact that it uses a microprocessor to carry out its functions. 

As explained above, each amendment was added for the purpose of showing that the 636 patent

contained a function not present in the prior art and each equivalent in question was being

claimed to essentially do that function in question, just through the use of a microprocessor. The

purpose of the amendments and their related equivalents were far from tangentially related, 

Case 2:04-cv-03925-RK Document 102 Filed 10/19/06 Page 31 of 33
32

rather, they were directly related. Therefore, Agrizap cannot rebut the presumption of

prosecution history estoppel and is prohibited, as a matter of law, from claiming infringement

under the doctrine of equivalents. Summary judgment on the doctrine of equivalents is thus

granted in Woodstream’s favor. 

IV. CONCLUSION

The evidence provided by both parties’ experts demonstrate that there are genuine issues

of material fact as to the literal infringement of the 636 patent by Woodstream. Agrizap could

not rebut the presumption of prosecution history estoppel and is barred from claiming

infringement under the doctrine of equivalents. Therefore, Woodstream’s Motion for Partial

Summary Judgment of Patent Noninfringement is denied as to literal infringement and granted as

to the doctrine of equivalents 

An appropriate Order follows.

Case 2:04-cv-03925-RK Document 102 Filed 10/19/06 Page 32 of 33
 IN THE UNITED STATES DISTRICT COURT

FOR THE EASTERN DISTRICT OF PENNSYLVANIA

____________________________________

:

AGRIZAP, INC., : CIVIL ACTION

:

Plaintiff, :

:

v. : No. 04-3925

:

WOODSTREAM CORPORATION, et al., :

:

Defendants. :

____________________________________:

O R D E R

AND NOW this 19th day of October, 2006, upon consideration of the Defendant

Woodstream’s Motion for Partial Summary Judgment on Patent Noninfringement, and the

Responses and Replies thereto, it is hereby ORDERED that:

1. Woodstream’s Motion for Partial Summary Judgment (Doc. No. 91) is

DENIED as to Agrizap’s literal infringement claim; and

2. Woodstream’s Motion for Partial Summary Judgment (Doc. No. 91) is

GRANTED as to Agrizap’s infringement claim under the doctrine of

equivalents.

BY THE COURT:

 /s/ Robert F. Kelly 

ROBERT F. KELLY, Sr. J.

Case 2:04-cv-03925-RK Document 102 Filed 10/19/06 Page 33 of 33