ll. 2-3. Thus, as explained in the discussion of Claims 1 and 59,
the ‘900 patent requires that successive entry of the same control
code have no effect whatsoever on the operating condition of the
controlled device. If, as Jackson concedes, “different [sequence
detection] signals are generated” in the MVP using the same toggled
touch-tone key pattern (Resp. at 13), then it cannot be true that the
MVP “only changes its state when it receives a sequence detection
signal selectively associated with its opposite state,” CC Order,
Chart at 2. This is because, as emphasized above, the “sequence
detection signal selectively associated with [a device’s] opposite
state” can only be generated in the ‘900 patent by entering a
different control code. Through toggling, the MVP can change its
operating condition upon repetitive entry of the same control code,
and this takes it outside the functional scope of the flip-flop means
in Claims 3 and 69.

As a matter of law, therefore, no reasonable jury could conclude
that the MVP performs the identical, or an equivalent, function of
the flip-flop means. Accordingly, Glenayre’s motion for summary
judgment with respect to Claims 3 and 69 is granted.

Claims 5 and 79

Glenayre next claims that Jackson has failed to create a genuine
issue as to whether the structural components within the MVP
(including any algorithm(s) used by its microprocessor(s)) are
programmed to perform the function of the “access limiting circuit

means” in substantially the same way as the corresponding individual

- 19 -



Order, that “the gating means . . . prevent/[s] the production of a
given sequence detection signal if the device is already in the state
associated with that signal and the same tone sequence is entered a
second time” means that a successive entry of the same control code
(for example, “*,1” followed by “*,1”) will not cause any control
response whatsoever in the controlled device. Put simply, there can
be no control signal (and therefore no change in the state of the
controlled device) without a predicate sequence detection signal.
This articulation of the basic schema of the ‘900 patent makes
plain the error of Jackson’s position. He is contending that the MVP
performs the function of the gating means simply because a different
control signal results from a successive entry of the same control
sequence. But the claimed function of the gating means in Claims 1
and 59 is not to produce a different control signal in response to
the same control sequence, it is to “disablf[e]” outright the
production of a given sequence detection signal (i.e., the one
corresponding to the control sequence entered) and thereby to disable
the production of any control signal in response to a successive
entry of the same control sequence. In the ‘900 patent, entering a
given control code a second consecutive time is a non-event. Not so
with the MVP. Because successive entry of the touch tone “1” causes
the MVP to respond, it follows that the sequence detection signal
associated with the tone entry “1” (which, in the language of the
‘900 patent, would be the relevant “predetermined sequence of
predetermined tone signals” or control code) has not been disabled.

- 13 -


entered correctly. In the MVP, the collection of access codes
involves three separate microprocessors: the central controller, one
of several time space controllers (“TSC”), and one of several digital
signal processors (“DSP”). (See generally Bettis Decl. at 44 14-20.)
The central processor first determines whether an access code is
necessary; if so, it recalls the number of digits in the access code
from a database and instructs the TSC to collect that number of
digits. The DSP detects and decodes the touch-tones as they are
entered, sending them to the TSC as 5-bit data packages. The TSC
continues collecting digits until it either reaches the number of
digits instructed by the central processor or until the subscriber
enters “#.” Once either event has occurred, the TSC forwards the
string of digits (along with certain other identifying information)
to the central processor. The central processor then recalls from
memory the access code for that subscriber and compares the string of
digits it has received from the TSC with the correct access code. If
they match, the central processor grants the caller access to the
main menu associated with that subscriber; if not, access is denied.
In bringing the instant motion, Glenayre does not contest that
the MVP performs the identical, or an equivalent, function of the
access limiting circuit means (which, as explained, is to prevent
access to the system unless an access code is first received)
Rather, Glenayre only tenders arguments related to structure. First,
Glenayre argues in its reply brief that Jackson has failed to

identify “precisely what structure in the Glenayre MVP is supposedly

- 23 -



and allows a user to retrieve voice mail and to execute various other
functions by using touch-tone commands.
LEGAL STANDARDS
Motion for Summary Judgment

Summary judgment is appropriate where “the pleadings,
depositions, answers to interrogatories, and admissions on file,
together with affidavits, if any, show that there is no genuine issue
as to any material fact and that the moving party is entitled to
judgment as a matter of law.” FED.R.Civ.P. 56(c). A fact is
“material” if it could affect the outcome of the suit under the
governing law; a dispute is “genuine” where the evidence is such that
a reasonable jury could return a verdict for the nonmoving party.
Anderson v. Liberty Lobby, Inc., 477 U.S. 242, 248 (1986). The
Supreme Court has emphasized “that at the summary judgment stage the
judge’s function is not himself to weigh the evidence and determine
the truth of the matter but to determine whether there is a genuine
issue [of material fact] for trial.” Id. at 249. In performing this
task, all factual disputes are resolved, and all reasonable
inferences are drawn, in favor of the nonmoving party. Jackson v.
Illinois Medi-Car, Inc., 300 F.3d 760, 764 (7th Cir. 2002). However,
“[slelf-serving assertions without factual support in the record will
not defeat a motion for summary judgment.” Jones v. Merchants Nat’1l
Bank & Trust Co., 42 F.3d 1054, 1058 (7th Cir. 1994).

The burden is initially upon the movant to identify those
portions of “the pleadings, depositions, answers to interrogatories,

-4-


To the extent Jackson’s motion to strike raises other issues, it
is denied.
CONCLUSION
For the foregoing reasons, Glenayre’s Motion for Summary

Judgment with respect to Claims 1, 3, 15, 69 and 112 of the ‘900

patent is GRANTED. Glenayre’s Motign for/ Summary Judgment with

respect to Claims 5 and 793 of the ‘900 patgént is DENIED. Jackson’s

Motion to Strike is GRANTED IN PART) AND DENIED IN PART.

IT IS SO ORDERED.

Harry D. Leinenweber, Judge
United States District Court

sate: “ebay LE 3003

- 34 -



digital logic circuit elements described in the ‘900 patent. While
it is a close calli, the Court holds that a genuine issue exists on
this point.

Claims 5 and 79 call for an “access limiting circuit means
coupled with said detecting means for preventing production of said
sequence detection signal until an access sequence comprising a
further predetermined sequence of predetermined tone signals is first
received on said phone line.” ‘900 Patent Reexamination Cert. B2,
col. 3, 11. 58 - 66, col. 22, 11. 31-38. In its CC Order, the Court
construed the function of the access limiting circuit means as
follows:

According to the plain language of the claim, the function

of the ‘900 patent’s access limiting circuit means is to

prevent a sequence detection signal from being produced

until after the phone line receives a predetermined
sequence of predetermined tone signals. In essence, it is

the function of the access limiting circuit means to

prevent a user from accessing a mailbox unless she first

enters an access code.
CC Order, Chart at 5 (internal quotation marks omitted). The Court
also held that the following structures correspond to the access
limiting circuit means:

Break-in prevention system 25; relay 90 and integrated

circuits including AND gates 55, 100, 102, 104, 108, 112,

116, 118 and 126, OR gates 85 and 120, exclusive OR gate

95, flip-flops 106, 110, 114 and 122, counters 70 and 124,

buffer 88, inverter 125.

Id.
In the preferred embodiment of the ‘900 patent, the required

access code - which is comprised of “touch-tone signals corresponding

- 20 -


Claims 15 and 112

Finally, Glenayre argues that Jackson has failed to set forth
evidence from which a reasonable jury could conclude that the MVP
performs the identical, or an equivalent, function of either the
“counter means” or the “disabling circuit means.” Glenayre is
correct.

Claims 15 and 112 describe a: (i) “counter means for producing
a count signal upon counting a predetermined number of received tone
signals greater in number than the number of tone signals in said
access sequence,” ‘900 Patent Reexamination Cert. B2, col. 5, ll. 62-
66, col. 30, ll. 49-53; and (ii) “disabling circuit means responsive
to said count signal and said gate signal for disabling production of
said sequence detection signal when said access sequence is not
present in said predetermined number of received tone signal[s],”
id., col. 5, 1. 67 - col. 6, 1. 4, col. 30, 11. 54-59. In its CC
Order, the Court held that “[i]t is the function of the counter means
to produce a count signal upon counting a predetermined number of
received tone signals greater in number than the number of tone
signals in the access sequence.” CC Order, Chart at 7. The Court
held that “[i]t is the function of the disabling circuit means to
disable production of a sequence detection signal if the access
sequence is not present in the predetermined number of tone signals
counted by the counter means.” Id.

As indicated in the previous discussion of Claims 5 and 79, the

device disclosed in the ‘900 patent will not respond unless at least

-~ 26 -



recognized entry of the three digits of the access code, the logic 1
output of these three flip-flops is loaded into a final flip-flop
122. Meanwhile, as the access code was being entered, a component
referred to as “counter 124” has been counting the number of tones
coming in; once four tones have been entered, counter 124 clocks
flip-flop 122. If flip-flop 122 has the logic 1 loaded at the time
it is clocked by counter 124 (as it would in the foregoing example),
it then permits the sequence detection means to begin detecting
signals (i.e., the user is allowed access to the system).

If, however, the user had incorrectly entered the access code as
“7, 8, 5, x,” a logic 1 would not have been clocked at the Q output
of flip-flop 110, and therefore not at the Q output of flip-flop 114.
As a result, the structure of the access limiting circuit means would
not have recognized entry of the digit “5.” Since a logic 1 would
not have been clocked through the entire chain of flip-flops (from
106 to 110 to 114) and loaded into the endpoint at flip-flop 122
this access code entry failure would ultimately mean that the
sequence detection means would be prevented from detecting signals
(i.e., the user would be denied access to the system). As Dr. Silva
put it, “[i]f an incorrect digit is entered after a correct digit is
entered, a ‘zero’ will be passed along the counter chain and
eventually deny access to the user.” (Silva Dep. 7 28.)

In contrast, the MVP does not check each digit of the access
code (or “password”) as it is entered and does not defer checking

subsequent digits of the access code until the earlier digits are

- 22 -


operating condition.” Id. Thus, in the present example, to turn the
controlled device off one would need to enter the “sequence detection
signal selectively associated with its opposite state”, i.e., “#, 1”
for “off.” Id. “Neither the hanging up of the answering circuitry

nor any other signal or operation can cause [the] flip-flop
means . . . to change its state.” Id.

In the MVP, certain conditions that are arguably “bistable” are
“controlled exclusively by toggling the feature on or off through
entry of the same command, not through entry of a different command.”
(Mot. Summ. J. at 14.) For example, Jackson notes that in the MVP
the “date and time stamp” may be turned on and off by successively
entering the touch-tone key pattern “4, 4, 2, 3.” Likewise with
certain other customizable features, such as message notification
(“4, 4, 3”) and constant touch (“5, 1%). One apparent benefit of
this operating procedure is that it eliminates the need to use (and
therefore keep track of) more than one control code.

Jackson argues, unconvincingly, that Glenayre’s “toggling
technique” is within the scope of Claims 3 and 69. He does so by
suggesting that, even though the MVP can control bistable operations
through the entry of the same control sequence, the MVP is
nevertheless “us{ing] different internal signals for ‘on’ and ‘off,’
even when the same DTMF key pattern is used to toggle.” (Resp. at 14
(emphasis supplied) .) Jackson continues: “For instance, the date
and time stamp DTMF key pattern [4]{4][2][3] will produce the ‘turn

date and time stamp on’ signal only when the pre-existing state of

-17-


Univ., 307 F.3d 1351, 1358 (Fed. Cir. 2002). As the patent owner,
Jackson bears the burden of proving infringement. Under Sea Indus.,
Inc. v. Dacor Corp., 833 F.2d 1551, 1557 (Fed. Cir. 1987) (“The
burden always is on the patentee to show infringement.”).

As noted at the outset of this opinion, the ‘900 patent
describes a system made up of hard-wired, digital logic circuit
elements. The MVP does not use hard-wired circuitry, instead
implementing its voice messaging services through programmed
microprocessors. It is therefore incontrovertible that the MVP does
not contain structure(s) “identical . . . to the corresponding
structure in the specification,” Odetics, Inc., 185 F.3d at 1267
(emphasis supplied), of the ‘900 patent. From the standpoint of
structure, then, Jackson must resort to proof of structural
equivalency, which, as previously discussed, will depend on whether
any differences between the structure(s) of the MVP and the
structure(s) disclosed in the specification of the ‘900 patent are
“insubstantial.” With respect to function, however, Jackson is free
to pursue theories of identity and/or equivalency.

Thus, to prevail in this action for any given claim of the ‘900
patent, Jackson must prove that the MVP is programmed to perform the
identical or equivalent functions recited in that claim. Further,
Jackson must identify the particular components within the MVP
(including any algorithm(s) used by its microprocessor(s)) that
allegedly perform those functions, and he must show that those

components are programmed to perform those functions in substantially

~9-


circuit means. Accordingly, Glenayre’s motion for summary judgment
with respect to Claims 15 and 112 is granted.
MOTION TO STRIKE

One final ancillary matter must be resolved. On January 14,
2003, Jackson filed a “motion to strike” certain arguments that
Jackson claims were raised for the first time in Glenayre’s reply
brief. In particular, Jackson claims that Glenayre’s reply brief
impermissibly argued for the first time that Jackson’s interpretation
of the range of ‘900 patent equivalents would ensnare the prior art
(specifically, the prior art of U.S. Patent No. 4,371,752). Cf. Tate
Access Floors, Inc. v. Interface Architectural Res., Inc., 279 F.3d
1357, 1367 (Fed. Cir. 2002) (“[T]he doctrine of equivalents cannot
extend so broadly as to ensnare prior art.”) Jackson is correct.
Because this argument was first raised in reply, it is waived. See
Highsmith v. Chrysler Credit Corp., 18 F.3d 434, 439 (7th Cir.
1994) (‘In most circumstances, a litigant who fails to raise an
argument until his reply brief will be deemed to have waived that
argument.”); Edwards v. Honeywell, Inc., 960 F.2d 673, 674 (7th Cir.
1992) (district court may not grant summary judgment on ground first
raised in reply). The fact that Jackson would bear the ultimate
burden of proof on the ensnarement issue does not excuse Glenayre
from properly raising it in its motion for summary judgment, thereby
allowing Jackson, and the Court, the benefit of a full response. Cf.

Celotex Corp., 477 U.S. at 323 (“[A] party seeking summary judgment

- 32 -



signals greater in number than the number of tone signals in said
access sequence” before accepting control commands.

“[T]he MVP allows three chances for a caller to get the password
right.” (Silva Decl. 4 27.) A “chance” in this context means a
predetermined time period. Thus, if we were to set each time period
at five seconds, a subscriber dialing up the MVP would be prompted
for a password and then given three discrete, five-second periods
within which to enter it correctly. If the subscriber accurately
entered the password during the first time period, access to the
system would be granted. If not, the subscriber would be given
another five-second time period to enter the password, and so on
through the third attempt. The MVP will automatically disconnect if
a caller fails successfully to enter the proper access code within
three attempts. (Reply at 17; cf. Bettis Dep. at p. 175, 1. 22 - p.
177, 1. 10.)

Jackson contends that this particular modus operandi is covered
by the counter means and the disabling circuit means in the case

where a subscriber has entered a password incorrectly the

first (or the first and second) time, but then gets it
vight the second (or third) time. . . . [I]n those
situations, the MVP (namely, the TSC part of the MVP) has
counted two or three times the number of tones in the
access sequence before permitting access. If a password

were four digits, for example, a person who got it wrong

the first time but right the third time has made the TSC

part of the MVP count twelve tones.

(Resp. at 21 (emphasis in original).) This is a specious argument
that rests on the well-worn logical fallacy post hoc ergo propter

hoc.

- 29 -



case are “means-plus-function” claims. They are therefore governed

by 35 U.S.C. § 112, 9 6, which provides as follows:
An element in a claim for a combination may be
expressed as a méans or step for performing a
specified function without the recital of
structure, material, or acts in support thereof,
and such claim shall be construed to cover the
corresponding structure, material, or acts
described in the specification and equivalents
thereof.

35 U.S.C. § 112, J 6.

“Literal infringement of a § 112, {1 6 limitation requires that
the relevant structure in the accused device perform the identical
function recited in the claim and be identical or equivalent to the
corresponding structure in the specification. Functional identity
and either structural identity or equivalence are both necessary.”
Odetics, Inc. v. Storage Tech. Corp., 185 F.3d 1259, 1267 (Fed. Cir.
1999) (citations omitted; emphasis in original). As Judge Gettleman
likewise framed the standard in Casio Phonemate, Inc: In order “‘to
meet a means-plus-function limitation, an accused device must (1)
perform the identical function recited in the means limitation and
(2) perform that function using the structure disclosed in the
specification or an equivalent structure.’” Casio Phonemate, Inc
105 F. Supp. 2d at 863-64 (quoting Carroll Touch, Inc. v. Electro
Mech. Sys., Inc., 15 F.3d 1573, 1578 (Fed. Cir. 1993)). Structural
equivalence for purposes of Section 112, Paragraph 6 turns on

“whether the differences between the structure in the accused device

and any disclosed in the specification are insubstantial.” Valmont


and admissions on file, together with the affidavits,” if any, that
the moving party believes demonstrate an absence of a genuine issue
of material fact. Celotex v. Catrett, 477 U.S. 317, 323 (1986).
Once the moving party has met this burden, the nonmoving party may
not rest upon the mere allegations contained in the nonmoving party’s
pleading, but rather “must set forth specific facts showing that
there is a genuine issue for trial.” fFrep.R.Civ.P. 56(e); Becker v.
Tenenbaum-Hill Assoc., Inc., 914 F.2d 107, 110 (7th Cir. 1990);
Schroeder v. Lufthansa German Airlines, 875 F.2d 613, 620 (7th Cir.
1989). Accordingly, summary judgment is mandatory “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, 477 U.S. at 322.
As the Federal Circuit has noted in the context of patent cases, “the
motion of an accused infringer for judgment on the ground of
non-infringement of a patent may be granted where the patentee’s
proof is deficient in meeting an essential part of the legal standard
for infringement.” UJohnston v. IVAC Corp., 885 F.2d 1574, 1577 (Fed.
Cir. 1989). In such a situation, there can be “‘no genuine issue as
to any material fact’, since a complete failure of proof concerning
an essential element of the nonmoving party’s case necessarily
renders all other facts immaterial.” Celotex, 477 U.S. at 323.
Infringement Criteria

Evaluating an infringement allegation requires comparing the

construed claim to the accused device. The claims at issue in this

-5-


the date and time stamp is ‘off;’ it will produce the different ‘turn
date and time stamp off’ signal only when the pre-existing state of

the date and time stamp is ‘on.’” (Id. at 13 (emphasis in original) .)

Jackson’s argument is nonsense and betrays a basic
misunderstanding of the ‘900 patent’s limitations. Jackson's key
conceptual error is his attempt to cleave the critical connection in
the ‘900 Patent between a “control sequence” (consisting of a
particular predetermined sequence of predetermined tone signals such
as “*,1”) and its corresponding “internal [sequence detection]
signal.” Jackson wants to argue that the ‘900 patent somehow reads
on devices that use the same control sequence to change a device from
one bistable operating condition to another (e.g., toggling the MVP’s
“date and time stamp” feature on and off by successive entry of the
key pattern [4][4}][2][3]). If Jackson’s argument were valid, it
would mean that, in the ‘900 patent, after a user had entered “*,1”
and turned a device on, a successive entry of “*,1” could turn the
device off by somehow stimulating a different “internal” sequence
detection signal. Such a conception is at manifest odds with the
plain meaning of the ‘900 patent.

In the ‘900 patent, a given sequence detection signal can only
be produced by entering a particular control code. See ‘900 Patent
Reexamination Cert. B2, col. 1, 1. 64 - col. 2, 1. 1. A “control
signal” causing the controlled instrument to alter its state (say,
from “off” to “on”) will only be produced in response to the

production of a given sequence detection signal. See id., col. 2,

- 18 -


structure is substantially different from that described by the claim
limitation, equivalence is not established.” Odetics, Inc., 185 F.3d
at 1267.

As the Supreme Court has observed, the statutory infringement
standard of 35 U.S.C. § 112, 4 6 is simply “an application of the
doctrine of equivalents in a restrictive role.” Warner-Jenkinson
Co., 520 U.S. at 28. Indeed, the only meaningful difference between
the infringement analysis under 35 U.S.C. § 112, 4 6 and the doctrine
of equivalents is that, under the statutory standard, “functional
identity is required.” Odetics, Inc., 185 F.3d at 1267 (emphasis in
original).

The content of the test for insubstantial differences under

§ 112, 4 6 thus reduces to “way” and “result.”. .

Structural equivalence under § 112, 4 6 is met only if the

differences are insubstantial; that is, if the assertedly

equivalent structure performs the claimed function in
substantially the same way to achieve substantially the

same result as the corresponding structure described in the

specification.

Id.; Caterpillar Inc. v. Deere & Co., 224 F.3d 1374, 1379 (Fed. Cir.
2000) (YA reduced version of the well-known tripartite test for the
doctrine of equivalents has been applied in the § 112, 4 6 context to
determine if the differences are insubstantial; an accused device is
equivalent when it performs the identical function in substantially
the same way to achieve substantially the same result.”)

Burden of Proof

“The determination of infringement, whether literal or under the

doctrine of equivalents, is a question of fact.” Madey v. Duke


equivalent to the access limiting circuit means.” (Reply at 15.)
This appears to be a demand that Jackson point to the particular
components within the MVP that allegedly perform the function of the
access limiting circuit means. As such, this argument comes too
late, see Stark v. PPM America, Inc., 2002 WL 31155083, at *7 (N.D.
Ill. Sept. 26, 2002) (summary judgment movant cannot raise new
arguments or legal theories in reply brief), and in any event is not
convincing, as Dr. Silva has highlighted (or at least sufficiently so
to survive summary judgment) the specific structures in the MVP that
assertedly perform the function of the access limiting circuit means
(see Silva Decl. %@ 26; Silva Fed.R.Civ.P. 26(a) (2) Expert Report).
Glenayre’s second (and only other) argument is that no reasonable
jury could conclude that the MVP and the structure disclosed in the
‘900 patent perform that function in substantially the same way. Put
more precisely, Glenayre claims that no reasonable jury could
conclude that the MVP’s string-compare password validation technique
is insubstantially different than the ‘900 patent’s one-digit-at-a-
time password validation technique.

In analyzing disputes of this nature at the summary judgment
stage, the Federal Circuit has admonished district courts not to
“conduct[] an impermissible component-by-component analysis to
determine that no reasonable jury could find structural equivalence.”
Caterpillar Inc., 224 F.3d at 1380. “It is of course axiomatic that
each element contained in a patent claim is deemed material to

determining the scope of the patented invention.” Odetics, 185 F.3d

- 24 -


Minute Ordes Fors (0697)

United States District Court, Northern District of Illinois

Name of Assigned Judge

Harry D. Leinenweber Sitting Judge if Other

WAP

or Magistrate Judge than Assigned Judge
CASE NUMBER 02 C 0256 DATE 2/18/2003
CASE Glenayre Electronics, Inc., vs. Philip Jackson
TITLE
{In the following box (a) indicate the party filing the motion, e.g... plaintiff. defendant. 3rd party plaintit®. andl (1p) state briefly the nature
MOTION: of the motion being presented.]
DOCKET ENTRY:
(ap) oO Filed motion of [ use listing in “Motion” box above.]
Q Oo Brief in support of motion due__
(3) oO Answer brief to motion due_ . Reply to answer brief due.
(4) a) Ruling/Hearing on set for at
6 Oo Status hearing[held/continued to] [set for/re-set for] on set for at
(6) Oo Pretrial conference[held/continued to} [set for/re-set for] on set for at
(7) Oo Trial[set for/re-set for} on at
(8) a [Bench/Jury trial] [Hearing] held/continued to at
o a This case is dismissed [with/without] prejudice and without costs[by/agreement/pursuant to]
OFRCP4im) CO Local Rule 41.1 COFRCP41(a)(1) 0 FRCP41(a)(2).
ral) ee | [Other docket entry) ENTER MEMORANDUM OPINION AND ORDER: Glenayre’s Motion for
Summary Judgment with respect to Claims 1, 3, 15, 59, 69 and 112 of the ‘900 patent is GRANTED.
Glenayre’s Motion for Summary Judgment with respect to Claims 5 and 79 of the 900 patent is DENIED.
Jackson’s Motion to Strike is GRANTED IN PART AND DENIED IN PART.
qi) @ [For further detail see order attached to the original minute order.]
No notices required. advised ia open court Document
No notices required. Number
unnber of notices
Notices mailed by jud lL 1 2003
Notilied counsel by telephone. FEB 19a
VY | Docketing to mail notices. ‘ Sou
Mall AO 450 form, abode dpfuivitals
Copy to juddge/magistrate judge.
Yb gases date wailed notice

initials

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ceived in
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deputy initials



second detection signals respectively in response to said second
control signal and said first control signal, respectively, whereby
said apparatus cannot produce said first detection signal and said
second detection signal at the same time.” ‘900 Patent Reexamination
Cert. B2, col, 2, 11. 25-33, col. 16, 11. 22-30 (emphasis supplied).
In its CC Order, the Court construed the function of the gating means
as follows: “It is the function of the gating means to prevent the
production of a given sequence detection signal if the device is
already in the state associated with that signal and the same tone
sequence is entered a second time.” CC Order, Chart at 2 (internal
quotation marks omitted; emphasis supplied). As described by Judge

Gettleman:

The language of Claim 1 and the detailed description
explain that entering a predetermined sequence of
predetermined tone signals (such as the tones # and 1),
produces a corresponding sequence detection signal, and a
certain gate and flip-flop respond by producing the control
signal “off,” thus turning off the device the patented
invention is controlling. Similarly, entering a
predetermined sequence of predetermined tone signals (such
as the tones * and 1), leads to the production of a
sequence detection signal, which itself leads to the
production of a corresponding control signal (such as
on”), thus turning on the controlled device.

According to the detailed description, the gating means
“assures that repetition of the ‘# ,1’ (off) sequence will
not result in turning the instrument on.” Similarly, the
gating means “prevents production of the ‘on’ signals
unless the instrument is in the off state. Hence,
repetition of the sequence ‘*,1% will not turn the
instrument ‘off,’ if it is already in the ‘on’ state.”

Casio Phonemate, Inc, 105 F. Supp. 2d at 865 (quoting ‘900 Patent,

col. 6, 11. 18-20, 33-36). Without the gating means, the controlled

-11-


the same way as the corresponding individual digital logic circuit
elements described in the ‘900 patent. Cf. generally id. at 1267-68.
DISCUSSION
Counterpart Claims

Before turning to the substance of the disputed claims in this
case, the Court notes (as it did in its CC Order) that Claims 1, 3,
5 and 15 are, in relevant part, linguistically identical to their
counterpart Claims 59, 69, 79 and 112. The only differences are
that, in the latter group of claims, “tone signals” are specified as
“DTMF tone signals” and each of the various means is specified as an
“integrated circuit” means (e.g., claim 1 describes a “control
means,” whereas claim 59 describes an “integrated circuit control
means”). For purposes of the instant Motion for Summary Judgment,
these slight syntactical asymmetries are immaterial. Accordingly,
the Court will handle each claim and its counterpart under a single
heading.

Claims 1 and 59

Glenayre contends that the MVP does not perform the function of
the “gating means.” That is, couched in the more precise language of
the summary judgment standard, Glenayre claims that Jackson has
failed to adduce evidence from which a reasonable jury could conclude
that the MVP performs either the identical, or an equivalent,
function of the gating means. Glenayre is correct.

Independent claims 1 and 59 each call for a “gating means
coupled in circuit for disabling production of said first and said

-10-



entered as part of its password validation procedure, it does not
follow that the tones constituting a previously misentered password
are “counted” for purposes of password validation in any subsequent
discrete time period. A simple analogy might help emphasize this
distinction: Suppose I am playing a carnival game in which I am
promised a prize if I can toss three balls into a basket. I am
allowed three tries, and on each try I am given just three balls.
All three of the balls must land in the basket during a single,
discrete try for me to win; if I fail to toss all three balls into
the basket on a given try, they are all handed back to me. Suppose
that I fail in my first and second attempts, but succeed in my third.
The carney then hands over the prize and I walk away a winner. The
critical point in this analogy is that I won the prize not because of
anything that happened in my first or second attempts, but only
because of my successful, self-contained third attempt. While I am
playing the game, the carney is only “counting” two things: the
number of balls that I land in the basket on any given try (three in
is a winner), and the number of tries I have used up at any given
point (three failed attempts and the game is over). The fact that I
may have landed some, or even none, of the balls in my first or
second attempts is totally irrelevant to my winning the prize.
Jackson has failed to adduce evidence from which a reasonable
jury could conclude that the MVP performs the identical, or an

equivalent, function of either the counter means or the disabling

- 31 -


The MVP is not “counting” previously misentered tone signals as
a precondition (in the form of a required number of “dummy tones”) to
accepting a password. Rather, the MVP is simply “counting” the
number of predetermined time periods that have been exhausted without
a successful password entry. After the third failed attempt, the MVP
disconnects the call. Suppose, for example, that my MVP password is
“7, 6, 5.” If I miskey my password as “7, 6, 4” during the first set
time period, the MVP will “count” that as one failure. If I again
enter “7, 6, 4” during the second time period, the MVP will “count”
that as a second failure. If I then finally get it right on the
third try and enter “7, 6, 5,” the MVP will allow me access to the
system, not because of any tone signals that I (mis)entered on the
first and second attempts - that is, not because the MVP has somehow
“count [ed] a predetermined number of received tone signals greater in
number than the number of tone signals in said access sequence” - but
rather because I entered the correct three-digit password during one
of the three distinct time periods allowed for password entry.

The only opposing “evidence” that Jackson offers to support his
argument is a single, highly conclusory statement from Dr. Silva to
the effect that, if an MVP subscriber doesn’t get his password right
until the second or third try, “the MVP . . . has counted two or
three times the number of tones in the access sequence before
permitting access.” (Silva Decl. 7 27.) Even to the extent this
statement is true, it is irrelevant. That is, while it might be said

that within each discrete time period the MVP “counts” the tones

- 30 -



Indus., Inc. v. Reinke Mfg. Co., 983 F.2d 1039, 1043 (Fed. Cir.
1993).

Based on the literal infringement standard just articulated, it
follows that if the accused device does not perform the identical
function specified in the means limitation, then “section 112,
paragraph 6... is not involved,” Pennwalt Corp. v. Durand-Wayland,
Inc., 833 F.2d 931, 934 (Fed. Cir. 1987), and there can be no finding
of literal infringement. However, the accused device might still be
found to infringe under the doctrine of equivalents if it “performs
substantially the same overall function or work, in substantially the
same way, to obtain substantially the same result as the claimed
invention.” Id. “{T]he doctrine of equivalents must be applied to
individual elements of the claim, not the invention as a whole.”
Warner-~Jenkinson Co. v. Holton Davis Chem. Co., 520 U.S. 17, 29
(1997). “{I]n order for a court to find infringement [under the
doctrine of equivalents], the [patent-holder] must show the presence
of every element or its substantial equivalent in the accused device.
To be a ‘substantial equivalent,’ the element substituted in the
accused device for the element set forth in the claim must not be
such as would substantially change the way in which the function of
the claimed invention is performed.” Perkin-Elmer Corp. v.
Westinghouse Elec. Corp., 822 F.2d 1528, 1533 (Fed. Cir.
1987) (citation and internal quotation marks omitted). “In the
doctrine of equivalents context, the following test is often used:

if the ‘function, way, or result’ of the assertedly substitute



to 7, 6, 5, x%, where x can be any signal at all (‘don’t care’ or
dummy signal),” ‘900 Patent, col. 8, 11. 21-23 - is recognized one
digit at a time. (Technically, this “access code” consists only of
the digits “7, 6, 5”; as will be discussed later in this opinion, the
entry of dummy signals, while necessary, is simply filler.) An
important consequence of this method of operation is that if a digit
in the access sequence is entered incorrectly, the structure of the
access limiting circuit means will not permit the circuitry to
recognize any subsequent digits of the access code that are entered.

If, for example, a user were to enter “7, 8, 5, x, the apparatus
described in the ‘900 patent would not recognize entry of the digit
yg”

Simplifying the relevant structure for purposes of explanation,
we can say that this one-digit-at-a-time verification procedure is
accomplished through a chain of three interlinked flip-flops (106,
110, and 114). See generally ‘900 Patent, col. 8, 1. 19 - col. 9, 1.
18; (Silva Dep. at 186-91, 196). Assuming “7, 6, 5, x” is the access
code, the apparatus of the ‘900 patent works as follows: If a user
initially enters a “7,” then a logic 1 is clocked at the Q output of
flip-flop 106. If the next digit entered is a “6,” then because the
previous digit (“7”) was also entered correctly, a logic 1 is clocked
at the Q output of flip-flop 110. Likewise with entry of the third
digit - if a “5” is entered, then because the previous digit (“6”)
was also entered correctly, a logic 1 is clocked at the Q output of

flip-flop 114. Once this chain of flip-flops has sequentially

-21-



one “dummy” tone is entered in addition to the access code. See ‘900
Patent, col. 8, ll. 19-23, col. 9, 11. 19-25. The rationale behind
dummy signals in the ‘900 patent is to allow the user flexibility in
creating a password and to provide greater protection against
unauthorized access to the system. Dr. Silva confirmed this
rationale at his deposition:

Q: Now, why would you want to count more than the number
of tone signals in the access sequence?

A: Well, there’s that - that gives you additional

protection. You can - you could have a system that would

- if you counted, it would just say, okay. I’11 let you

put in eight digits, but three in a row of them have to be

the right ones before I grant you access. It gives you —

well, let’s put it - protection isn’t such a good word. It

gives you a little bit of flexibility. You might miss the

- you might say I’m putting in my access code here, and I

think it’s 765, but it might be 7658. But I’m the

authorized user, and so it lets me put in an extra digit in

this particular example, and it won’t hurt anything.

(Silva Dep. 222, ll. 3-20.).

Although in the preferred embodiment of the ‘900 patent the
“access sequence compris[es] touch-tone signals corresponding to 7,
6, 5, x, where x can be any signal at all (‘don’t care’ or dummy
signal), . . . any number of signals in any given sequence may be
utilized, including any number of desired ‘don’t care’ or dummy
signals at any point in the sequence, without departing from the
invention.” See ‘900 Patent, col. 8, ll. 19-23, col.9, 11. 21-25.
For example, a user could designate a three-digit password that is

followed by seven dummy signals: “7, 6, 5, xX, xX, X, X, &%, X, X.

Then, even if an unauthorized user somehow obtained the password (“7,

- 27 -


The ‘900 patent works in the following way: When sequences
of two or more touch tones are entered into a telephone and
received over a telephone line, the controller of the ‘900
patent responds by generating “control signals.” The
process begins when the owner of the appliance controlled
by the ‘900 patent enters a specific “tone sequence,” such
as the sequence “*,1” or the sequence “# ,1.” (The sequence
“*,1” turns the controlled appliance on, while the sequence
“# ,1” turns the controlled appliance off.) The tone
sequences “*,1” and “# ,1” are two types of “control
codes.” The controller of the ‘900 patent includes a
“detecting means” that detects the control code the owner
has input. Once the control code is input and detected,
the controller outputs a corresponding “sequence detection
signal.” The sequence detection signal is then fed to a
bistable “control means” that always outputs either an “on”
control signal or an “off” control signal to the controlled
appliance. Consequently, if the owner enters the tone
sequence “*,1,” the ultimate result will be that the
controlied appliance will turn on; conversely, if the owner
enters the tone sequence, “# ,1,” the ultimate result will
be that the controlled appliance will turn off.

Casio Phonemate, Inc, 105 F. Supp. 2d at 861-62.

Glenayre manufactures and sells equipment to the
telecommunications industry, providing carrier grade devices to
network operators that, in turn, provide retail telephone services to
the public, Jackson claims that certain of Glenayre’s products, in
particular certain voice messaging or “voice mail” hardware and
software known as the MVP 2120 and MVP 4240 (together, the “MVP”)
(Am. Countercl. 9 13), infringe the ‘900 patent. The MVP is a
complex, multiple-microprocessor computer server which is used in the
central offices of telephone service providers (i.e., phone
companies) and interfaces with the telephone system at the trunk
level. The MVP can be accessed remotely from a standard touch-tone

telephone (in most cases after entry of an “access code” or password)


Given this, no reasonable jury could conclude that the MVP performs
the identical, or an equivalent, function of the gating means. Cf.
Casio Phonemate, Inc, 105 F. Supp. 2d at 867 (“{T]he accused device
does not prevent production of the sequence detection signal
associated with the tone sequence “*, 2.” Rather, every time the
tone sequence “*, 2” is entered, the accused device appears to detect
this sequence and respond to it. If the accused device does not
‘disabl[e] production of . . . detection signals,’ it does not have
a function identical to that of the gating means required by the ‘900
patent.”). Accordingly, Glenayre’s motion for summary judgment with
respect to Claims 1 and 59 is granted.
Claims 3 and 69

Glenayre next argues that no reasonable jury could conclude that
the MVP performs the identical, or an equivalent, function of the
“flip-flop means.” Glenayre is again correct.

Independent claims 3 and 69 describe a

flip-flop means associated with each said bistable
operation, with said flip-flop means producing first state
and second state output signals for each said bistable
operation, said first state output signal corresponding to
one of said mutually-exclusive operating conditions, and
said second state output signal corresponding to the other
of said mutually-exclusive operating conditions, and
wherein said flip~flop means is responsive to a sequence
detection signal selectively associated with one of said
conditions of fewer than all of said bistable operations
for changing from said first state output signal to said
second state output signal for said fewer than all of said
bistable operations and is responsive to a different
sequence detection signal selectively associated with the
other one of said conditions of fewer than all of said
bistable operations for changing from said second state
output signal to said first state output signal for said

- 14 -


when it receives a sequence detection signal[ ] selectively
associated with its opposite state.”

According to the plain language of the claim coupled with

the detailed description, if the appliance is on, for

example, it is part of the function of the flip-flop means

to not turn the item off until it receives the sequence

detection signal associated with the operating condition

“off.” When the flip-flop means receives this sequence

detection signal, it is part of the function of the flip-

flop means to produce an output signal corresponding to the

operating condition “off,” such as the control signal

“off.” It is also part of the function of the flip-flop

means to turn the item back on only if it receives a

different sequence detection signal, e.g., the sequence

detection signal selectively associated with the operating
condition “on.”
CC Order, Chart at 4 (internal quotation marks omitted; emphasis
supplied).

Based on this construction of the function of the flip-flop
means, repeating a control sequence (say, “*,1” followed immediately
by “*,1”) will not cause the controlled appliance to change its
operating state. To take an example, assume that a device being
controlled is currently in the operating state “off.” Entering the
control sequence “*,1” triggers the production of a corresponding
sequence detection signal, which in turn triggers the production of
the control signal “on,” which turns the device on. While the device

is in the “on” operating state, the flip-flop means functions to
ensure that successive entry of the “on” control sequence “*,1” will
not cause the device to turn off. Put another way, the flip-flop
means functions to maintain the operating state of the device and to
keep it in that condition “until and if and only if it receives the

sequence detection signal associated with the mutually exclusive

- 16 -



-

On September 27, 2002, the Court stayed Jackson’s counterclaim,
insofar as it is premised on theories of contributory infringement
and inducement, pending resolution of the direct infringement
allegations raised in this action. On November 21, 2002, the Court
issued its Claims Construction Order (the “CC Order”) construing the
meaning and scope of disputed Claims 1, 3, 5, 15, 59, 69, 79 and 112
of the ‘900 patent. Presently before the Court is Glenayre’s Motion
for Summary Judgment. For the following reasons, the motion is
granted in part and denied in part.
BACKGROUND

The ‘900 patent “discloses and claims a set of electronic
circuits for remotely controlling appliances or devices through the
use of tones produced by touch-tones telephones.” Jackson v. Thomson
Consumer Elecs., Inc., 139 F. Supp. 2d 1003, 1005 (S.D. Ind. 2001).
As ably described by Judge Gettleman in Jackson v. Casio Phonemate,
Inc., 105 F. Supp. 2d 858 (N.D. Ill. 2000):

{Jackson’s] invention can be connected to, for example, a

heating or air conditioning system or a lighting system,

and enables a caller to remotely control the attached

appliance. The caller can make the appliance perform a

number of functions by using a predetermined sequence of

tones, such as those tones generated by most telephones.

The preferred embodiment of the apparatus covered by the

‘900 patent responds to one predetermined sequence of

tones, known as the access code, and thereafter responds to

other predetermined sequences of tones, known as “control

codes” [occasionally referred to in this opinion as

“control sequences”], which are used, for example, to turn

the attached appliance on and off. {Jackson’s] apparatus

uses integrated circuit digital logic to perform its
functions.


at 1268. However, “[t}he individual components, if any, of an
overall structure that corresponds to the claimed function are not
claim limitations. Rather, the claim limitation is the overall
structure corresponding to the claimed function.” Id.

Given this cautionary guidance from the Federal Circuit, the
Court feels constrained to conclude that a genuine issue exists as to
whether the MVP performs the access limiting circuit means of
Claims 5 and 79 in “substantially the same way” as the structure
disclosed in the ‘900 patent. Based on the parties’ submissions, all
that can fairly be said at this point about the “overall structure
that corresponds to the claimed function” of the access limiting
circuit means is that it checks a user’s password one digit at a
time. The MVP, on the other hand, eschews the digit-by-digit
approach and instead checks a subscriber’s access code as a single
string of digits. While this shows a literal operational difference,
Glenayre has not persuaded the Court that its technique is
necessarily substantially different. Glenayre has not identified any
distinguishing advantages (for example, enhanced utility, greater
efficiency, etc.) that the MVP’s single-string procedure offers over
the digit-by-digit method described in the ‘900 patent, and the Court
is unable to discern any on its own. From the evidence made
available to the Court, a reasonable jury could find structural
equivalence between these two methods. Accordingly, Glenayre’s
motion for summary judgment with respect to Claims 5 and 79 is

denied.

- 25 -



5

IN THE UNITED STATES DISTRICT COURT
FOR THE NORTHERN DISTRICT OF ILLINOIS

EASTERN DIVISION

GLENAYRE ELECTRONICS, INC.,
Plaintiff,
v.
PHILIP JACKSON, an individual,

Defendant.

PHILIP JACKSON,
Counterclaim-Plaintiff,

Vv.

GLENAYRE ELECTRONICS, INC.,

METROCALL, INC., ARCH WIRELESS,

INC., PRIMECO PERSONAL

COMMUNICATIONS, L.P., and JOHN

DOES (1-10),

Counterclaim-Defendants.

FILED

FEB 1 8 2003

JUDGE HARRY D. LEINENWEBER
US. DISTRICT COURT JUDGE

Case No. 02 Cv 0256

Hon. Harry D. Leinenweber

MEMORANDUM OPINION AND ORDER

Plaintiff Glenayre Electronics,

action against defendant Philip Jackson (“Jackson”) seeking

Inc. (“Glenayre”) brings this

a

declaratory judgment that none of its products infringe any claim of

U.S. Patent No. 4,596,900” (the “*900 Patent”) (Compl. J 1) held by

Jackson. Jackson, by way

amended counterclaim filed

October 16, 2002, alleges in turn that “Glenayre has infringed at

least Claims 1, 3, 5, 15, 59,

79 and 112 of the ‘900 patent

through acts of direct infringement, contributory infringement and/or

inducement in violation of 35 U.S.C. § 271.” (Am. Countercl. @ 12.)

a


always “bears the initial responsibility of informing the district
court of the basis for its motion... .”).

Jackson also suggests that Glenayre failed to argue in its
motion for summary judgment that the MVP does not infringe the ‘900
patent under the doctrine of equivalents. This argument is not well~
taken. Glenayre’s complaint seeks a broad declaratory judgment of
non-infringement. (Compl. @ 1.) Jackson’s amended answer and
counterclaim alleges that Glenayre directly infringes the ‘900 patent
(Am. Countercl., 912.), and Jackson bears the burden of proof on this
issue, Under Sea Indus., Inc., 833 F.2d at 1557. It is elementary
that direct infringement must either be shown literally or through
the doctrine of equivalents. 69 C.J.S. Patents, § 400 (2002).
Indeed, the Court provided a detailed discussion in its CC Order of
both theories of infringement and noted that the core issue in this
case is whether Glenayre infringes the ‘900 patent either “literally
under 35 U.S.C. § 112, 4 6 or under the doctrine of equivalents.” CC
Order at 6. Glenayre’s properly supported motion for summary
judgment argues that Jackson has failed to make a showing sufficient
to establish direct infringement for each of the eight disputed
claims in this case. Glenayre is clearly challenging Jackson to
create a genuine issue of material fact on infringement either
literally or under the doctrine of equivalents. Accordingly,
Jackson’s motion to strike “Glenayre’s discussion of the doctrine of

equivalents” from its reply brief is denied.

- 33 -


6, 5”), he would be denied access to the system if he entered
anything fewer than ten digits.

The structure corresponding to the counter means - a component
dubbed “counter 124” - is responsible for counting the entry of tone
signals making up the access code and any required dummy signals;
upon receiving the appropriate number, it generates a “count signal”
which is fed to flip-flop 122. If the access code has otherwise been
properly entered, the device disclosed in the ‘900 patent will then
permit the production of sequence detection signals in response to
control codes (i.e., the user will be allowed access to the system).
If, however, “the access sequence is not present in the predetermined
number of tone signals counted by the counter means,” CC Order, Chart
at 7 (emphasis supplied), the disabling circuit means will prevent
the user from accessing the system.

In sharp contrast, the MVP does not require “dummy signals” to
be entered along with an access code before a subscriber is granted
access to its system. Rather, the TSC collects the exact number of
digits equal to a subscriber’s access code and then sends that string
to the central processor for validation. If the password matches,
access to the system is granted; if not, access is denied. If the
correct access code has been entered and the subscriber continues to
enter tone signals, the MVP will interpret those additional keyed
tones as control commands. Thus, phrased in the language of the ‘900

patent, the MVP does not count “a predetermined number of tone

- 28 -



device would “toggle” on or off irrespective of which control code
had been entered.

Turning now to the operation of the MVP, Jackson observes that

the MVP will “play a message” (the first message) when the

subscriber presses “1” at the beginning of a session.

While the message is playing (i.e., when the device is in

the state associated with the sequence detection signal for

“play first message” for that mailbox), several DTMF [dual-

tone multifrequency] key options are available. But

critically, when the subscriber presses “1” again, the

“play first messages” signal is not re-generated. Instead,

a very different signal is generated within the Glenayre

device, namely the “keep message new and play the next”

signal (i.e., a type of “skip message” signal).
(Resp. at 9-10 (citations omitted; emphasis in original).) From this
Jackson concludes that the MVP performs the identical, or an
equivalent, function of the gating means and thereby infringes the
‘900 patent. Jackson is entirely mistaken.

First, as a foundational matter, in the ‘900 patent each
“sequence detection signal” corresponds to a unique “predetermined
sequence of tone signals” (for example, “*,1”). See ‘900 Patent
Reexamination Cert. B2, col. 1, 1. 64 - col. 2, 1. 1. That
predetermined sequence of tone signals is known as a “control code”
or “control sequence.” By the terms of the ‘900 patent, a “control
signal” causing the controlled instrument to change its state (say,
from “off” to “on”) will only be produced in response to the
production of a given sequence detection signal. See id., col. 2,
ll. 2-3 (describing a “control means responsive to said sequence

detection signal for producing a corresponding control signal”

(emphasis supplied)). Thus, to say, as the Court did in its CC

-12-



fewer than all of said bistable operations, and maintaining
the state of said flip-flop means until and if and only if
said flip-flop means responds to a sequence detection
signal selectively associated with the other of said
conditions of fewer than all of said bistable operations,
said first and second state output signals comprising said
control signal.

‘900 Patent Reexamination Cert. B2, col. 2, 1. 66 - col. 3, 1. 30,
col. 19, 11. 23-52. In its CC Order, the Court concurred with Judge
Gettleman’s view of the function of the flip-flop means, construing
it as follows:

According to the plain language of Claim 3, the ‘900 patent
controls “bistable” operations, meaning operations that
have two mutually exclusive stable operating conditions
only. The two mutually exclusive operating conditions of
the preferred embodiment of [Jackson]'s patent are “on” and
“off.” As [Jackson] explained to the patent office on
April 26, 1996, “a single flip-flop means 66 selectively
controls both of two, mutually exclusive, stable operating
conditions (e.g., ‘ON’ and ‘OFF’) of a bistable operation.”
The language of Claim 3 and the detailed description
explain that entering a predetermined sequence of
predetermined tone signals (such as the tones # and 1),
produces a sequence detection signal, which itself produces
a corresponding control signal (such as “off”). As
explained in the claim language, a specific and different
sequence detection signal is associated with each of the
two operating conditions, and part of the function of the
flip-flop means is to respond to different sequence
detection signals in different ways.

The claim language reveals that it is also part of the
function of the flip- flop means to maintain its state and
remain in one operating condition (e.g., on) “until and if
and only if” it receives the sequence detection signal
associated with the mutually exclusive operating condition
(e.g., off). As [Jackson] explained while prosecuting the
patent: “flip-flop means 66 maintains its state until it
responds to a sequence detection signal selectively
associated with the other of its two mutually exclusive
states. Neither the hanging up of the answering circuitry
. . hor any other signal or operation can cause flip-flop
means 66 to change its state. It only changes its state

- 15 -