IN THE UNITED STATES DISTRICT COURT

FOR THE EASTERN DISTRICT OF TEXAS

MARSHALL DIVISION 

COBBLESTONE WIRELESS, LLC,

Plaintiff, CASE NO. 2:23-cv-00382

v. (Lead Case)

CELLCO PARTNERSHIP D/B/A VERIZON 

WIRELESS.,

JURY TRIAL DEMANDED

Defendants,

ERICSSON INC.,

Intervenor 

COBBLESTONE WIRELESS, LLC,

Plaintiff, CASE NO. 2:23-cv-00380

v. (Member Case)

AT&T MOBILITY LLC, AT&T SERVICES, 

INC., AND AT&T CORP., 

JURY TRIAL DEMANDED

Defendants,

ERICSSON INC.,

Intervenor 

COBBLESTONE WIRELESS, LLC,

Plaintiff, CASE NO. 2:23-cv-00381

(Member Case)

v.

T-MOBILE USA, INC. JURY TRIAL DEMANDED

Defendants,

ERICSSON INC.,

Intervenor 

MOVANT-INTERVENOR ERICSSON INC.’S

UNOPPOSED MOTION FOR LEAVE TO 

INTERVENE

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TABLE OF CONTENTS

I. INTRODUCTION ............................................................................................... 1

II. STATEMENT OF FACTS .................................................................................. 3

III. ARGUMENT....................................................................................................... 4

A. ERICSSON IS ENTITLED TO INTERVENE AS A MATTER OF 

RIGHT PURSUANT TO RULE 24(a)(2). .....................................................5

1. Ericsson’s Motion to Intervene Is Timely. ...............................................5

2. Ericsson Has a Significant Interest in the Property and Transactions 

at Issue in This Lawsuit. ...........................................................................7

3. Ericsson’s Ability to Protect Its Interests Will Be Impaired if It 

Cannot Intervene.......................................................................................7

4. AT&T Cannot Adequately Represent Ericsson’s Interests in 

Defending Against Cobblestone’s Infringement Allegations...................8

B. IN THE ALTERNATIVE, ERICSSON SHOULD BE PERMITTED 

TO INTERVENE PERMISSIVELY. .............................................................9

IV. CONCLUSION.................................................................................................. 11

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TABLE OF AUTHORITIES

Page(s)

CASES

Brumfield v. Dodd,

749 F.3d 339 (5th Cir. 2014) .........................................................................................4

Chandler & Price Co. v. Brandtjen & Kluge, Inc.,

296 U.S. 53 (1935).........................................................................................................2

City of Houston v. Am. Traffic Sols., Inc.,

668 F.3d 291 (5th Cir. 2012) .........................................................................................5

Codex Corp. v. Milgo Electronic Corp.,

553 F.2d 735, 737-38 USPQ 49 (1st Cir.), cert. denied, 434 U.S. 860, 54 L. 

Ed. 2d 133, 98 S. Ct. 185 (1977) ...................................................................................7

Edwards v. City of Houston,

78 F.3d 983 (5th Cir. 1996) (en banc) .......................................................................5, 6

Ericsson Inc. v. D-Link Sys., Inc.,

No. 6:10-cv-473 (E.D. Tex. May 4, 2012), Dkt. No. 205..............................................6

Heaton v. Monogram Credit Card Bank of Ga.,

297 F.3d 416 (5th Cir. 2002) .........................................................................................8

Intellectual Ventures I LLC v. AT&T Mobility LLC,

No. 12-193-LPS, 2014 U.S. Dist. LEXIS 125280 (D. Del. Sept. 8, 2014) 

(Stark, J.)........................................................................................................................7

Kahn v. Gen. Motors Corp.,

889 F.2d 1078 (Fed. Cir. 1989)......................................................................................2

Katz v. Lear Siegler, Inc.,

909 F.2d 1459 (Fed. Cir. 1990)..................................................................................2, 7

New Orleans Pub. Serv., Inc. v. United Gas Pipe Line Co.,

732 F.2d 452 (5th Cir. 1984) .......................................................................................10

Newby v. Enron Corp.,

443 F.3d 416 (5th Cir. 2006) .........................................................................................9

SEC v. U.S. Realty & Improvement Co.,

310 U.S. 434 (1940).......................................................................................................9

Sierra Club v. Espy,

18 F.3d 1202 (5th Cir. 1994) .........................................................................................4

Case 2:23-cv-00382-JRG-RSP Document 56 Filed 12/22/23 Page 3 of 17 PageID #: 353
iii

Sierra Club v. Glickman,

82 F.3d 106 (5th Cir. 1996) .......................................................................................7, 8

Stauffer v. Brooks Bros., Inc.,

619 F.3d 1321 (Fed. Cir. 2010)......................................................................................4

Sw. Bell Tel., L.P. v. Arthur Collins, Inc.,

No. 3:04-cv-669 (N.D. Tex. Jan. 28, 2005), Dkt. No. 50 ..........................................6, 8

Team Worldwide Corp. v. Wal-Mart Stores, Inc.,

No. 2:17-cv-00235-JRG, 2017 U.S. Dist. LEXIS 201769 (E.D. Tex. Dec. 7, 

2017) ..........................................................................................................................7, 8

Texas v. United States,

805 F.3d 653 (5th Cir. 2015) .............................................................................4, 5, 6, 8

TiVo Inc. v. AT & T Inc.,

No. 2:09-cv-259, 2010 U.S. Dist. LEXIS 146363 (E.D. Tex. Mar. 31, 2010)

..............................................................................................................................6, 9, 10

U.S. Ethernet Innovations, LLC v. Acer, Inc., 2010 U.S. Dist. LEXIS 150649, at 

*12................................................................................................................................10

Wal-Mart Stores, Inc. v. Tex. Alcoholic Bev. Comm'n,

834 F.3d 562 (5th Cir. 2016) .........................................................................................6

RULES

Federal Rule of Civil Procedure 24 ........................................................................... passim

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MOVANT-INTERVENOR ERICSSON INC.’S

UNOPPOSED MOTION FOR LEAVE TO INTERVENE

Pursuant to Federal Rule of Civil Procedure 24, Ericsson Inc. (“Ericsson”) moves for leave 

to intervene in the above-titled action against AT&T as of right under Rule 24(a)(2), or 

alternatively, with permission of the Court under Rule 24(b)(1)(B) to defend allegations of 

infringement with respect to its base stations that were provided to AT&T (“Ericsson’s Motion” 

or “Motion”).

1

I. INTRODUCTION

Plaintiff Cobblestone Wireless, LLC (“Cobblestone”) sued AT&T Services Inc., AT&T 

Mobility LLC, and AT&T Corp. (collectively, “Defendants” or “AT&T”), one of Ericsson’s 

customers, on August 25, 2023, asserting a single patent (the “Asserted Patent”) (Dkt. No. 1 (“Pl.’s 

Compl.”)).2 Ericsson seeks to intervene so that the dispute between Ericsson and Cobblestone may 

be efficiently disposed of in the pending proceeding. AT&T does not oppose this Motion and 

Cobblestone does not oppose Ericsson’s intervention to defend allegations of infringement with 

respect to Ericsson base stations.

In its complaint, Cobblestone alleges that AT&T infringes the Asserted Patent by

“mak[ing], us[ing], offer[ing] for sale, sell[ing], and/or import[ing] certain products and services, 

including cellular base stations, mobile products, and services that support 3GPP carrier 

aggregation” (Pl.’s Compl. ¶ 14).

1 In accordance with Federal Rule of Civil Procedure 24(c), a copy of Ericsson’s proposed Answer 

in Intervention and Counterclaims is attached as Exhibit 1.

2 On the same day, Cobblestone brought other actions including against Cellco Partnership d/b/a 

Verizon Wireless., Case No. 2:23-cv-00382, and T-Mobile USA, Inc., Case No. 2:23-cv-00381. 

Ericsson is filing a motion to intervene to defend allegations of infringement with respect to its 

LTE/5G base stations in the Verizon and T-Mobile cases on the same grounds as this Motion.

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Ericsson provides AT&T with certain types of network equipment, such as base stations, 

that allows AT&T to provide “mobile products, and services that support 3GPP carrier 

aggregation” that Cobblestone accused in its Complaint (id. ¶ 14). As a result, this case presents a 

justiciable controversy as to Ericsson. As a designer, manufacturer, and seller of certain base 

stations that support the Defendant’s cellular networks, Ericsson is in the best position to defend 

infringement claims directed to those products. “It is a simple fact of life that a manufacturer must 

protect its customers, either as a matter of contract, or good business, or in order to avoid the 

damaging impact of an adverse ruling against its products.” Katz v. Lear Siegler, Inc., 909 F.2d 

1459, 1464 (Fed. Cir. 1990); see also Chandler & Price Co. v. Brandtjen & Kluge, Inc., 296 U.S. 

53, 55 (1935) (noting a manufacturer’s intervention in infringement action against a customer is 

“necessary for the protection of its interest”). The Federal Circuit recognizes the importance of 

customer suits, such as this one, yielding to suits raising the same claims against the product 

manufacturer. See, e.g., Katz, 909 F.2d at 1464 (upholding stay of patent infringement suit against 

customers, stating “in reality, the manufacturer is the true defendant in the customer suit”); Kahn 

v. Gen. Motors Corp., 889 F.2d 1078, 1081 (Fed. Cir. 1989) (explaining the “customer suit 

exception” exists because a manufacturer has a “presumed greater interest in defending its actions 

against charges of patent infringement”).

Accordingly, Ericsson seeks to intervene because it sells equipment and technology to 

AT&T that AT&T uses, and Cobblestone has accused that use of infringement. As the designer, 

manufacturer, and distributor of accused equipment and technology, Ericsson has a substantial 

interest in the litigation and is in the best position to defend against certain of Cobblestone’s claims

with respect to its base stations. Ericsson’s Motion is timely, and no existing party will suffer 

prejudice if Ericsson intervenes. Moreover, Ericsson’s intervention to defend allegations of 

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infringement with respect to its base stations will not result in the case being delayed. Thus, 

Ericsson respectfully requests the Court’s permission to intervene to defend allegations of 

infringement with respect to Ericsson base stations as a matter of right under Rule 24(a) or, 

alternatively, that the Court allow intervention under Rule 24(b).

II. STATEMENT OF FACTS

Plaintiff Appears to Accuse AT&T Network Equipment Supplied to AT&T by 

Ericsson. Cobblestone accuses AT&T of infringing the Asserted Patent because of AT&T’s use 

of allegedly infringing cellular wireless networks and equipment (Pl.’s Compl. ¶ 14). Ericsson

supplies, among other things, equipment and technology incorporated by AT&T into these cellular 

networks. This network equipment and technology is required for AT&T’s cellular networks to 

function and allow AT&T’s customers to access the networks using their smartphones and other 

mobile equipment. In general, this network equipment and technology is interoperable with aspects 

of the technical standards promulgated by the 3rd Generation Partnership Project (“3GPP”). 

Ericsson is a member of 3GPP, and participated in the development of the standards.

Ericsson supplies several types of network equipment and technology to AT&T, and 

Ericsson’s entry into the case will facilitate discovery related to this equipment. For example, for 

the Ericsson-supplied equipment, the documents and other tangible evidence, including equipment 

specifications, likely reside with Ericsson. The technical know-how and testimony for this 

equipment also likely resides with Ericsson. As a result, Ericsson’s entry into the case should 

streamline and simplify this litigation, especially as it relates to the Ericsson-supplied network 

equipment and technology that supports AT&T’s cellular services, including Ericsson Supplied

Base Stations.

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In this case, Cobblestone identified AT&T’s cellular base stations as accused products.

Ericsson provides base stations to AT&T, and thus, Ericsson-supplied equipment, software and 

technology is integral to the resolution of this case. Ericsson has a substantial interest in protecting 

its technology.

This Case Is at an Early Stage in the Litigation. Currently, no activity has occurred in 

this case that weighs against intervention. Cobblestone filed its complaint on August 25, 2023 

(Dkt. No. 1) and AT&T answered on November 3, 2023 (Dkt. No. 25)3. The Court has not yet set 

dates for the scheduling conference, Markman hearing or trial for this case. As shown, this case is 

at an early stage and intervention will cause no harm or delay to Cobblestone. 

III. ARGUMENT

There are two mechanisms by which a non-party may intervene and participate in an action: 

intervention as of right and permissive intervention. Federal Rule of Civil Procedure 24(a) governs 

intervention by right, while Rule 24(b) governs intervention by permission. The issue of 

intervention is not unique to patent law, and therefore, the law of the regional circuit applies. 

Stauffer v. Brooks Bros., Inc., 619 F.3d 1321, 1328 (Fed. Cir. 2010) (reviewing a district court’s 

Rule 24 intervention decision under regional circuit law). Under Fifth Circuit law, intervention is 

permitted where “no one would be hurt, and the greater justice could be attained.” Texas v. United 

States, 805 F.3d 653, 657 (5th Cir. 2015) (quoting Sierra Club v. Espy, 18 F.3d 1202, 1205 (5th 

Cir. 1994)). “Although the movant bears the burden of establishing its right to intervene, Rule 24

is to be liberally construed.” Id. at 656 (emphasis added) (quoting Brumfield v. Dodd, 749 F.3d 

339, 341 (5th Cir. 2014)). Ericsson is entitled to intervene to defend against Cobblestone’s 

3 This docket entry was only entered in lead case Cobblestone Wireless v. Cellco Partnership d/b/a 

Verizon Wireless, Case No. 2:23-cv-00382.

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allegations of infringement with respect to Ericsson’s base stations as a matter of right and, 

therefore, respectfully requests that the Court grant the present motion under Rule 24(a)(2), or in 

the alternative, permissively pursuant to Fed. R. Civ. P. 24(b)(1)(B).

A. ERICSSON IS ENTITLED TO INTERVENE AS A MATTER OF 

RIGHT PURSUANT TO RULE 24(a)(2).

Under Rule 24(a)(2), a movant must be permitted to intervene as a matter of right whenever 

four conditions are met:

(1) the application for intervention is timely;

(2) the applicant has an interest relating to the property or transaction which is the subject 

of the action;

(3) the applicant is so situated that the disposition of the action may, as a practical matter, 

impair or impede his ability to protect that interest; and,

(4) the applicant’s interest is inadequately represented by the existing parties to the suit.

Fed. R. Civ. P. 24(a)(2); Texas, 805 F.3d at 657. This inquiry is “a flexible one,” which “must be 

measured by a practical rather than technical yardstick.” City of Houston v. Am. Traffic Sols., Inc., 

668 F.3d 291, 293 (5th Cir. 2012) (quoting Edwards v. City of Houston, 78 F.3d 983, 999 (5th Cir. 

1996) (en banc)). Ericsson meets the four requirements to intervene as of right under Rule 24(a).

1. Ericsson’s Motion to Intervene Is Timely.

Timeliness is determined from all the facts and circumstances of a particular case, 

including the time from notice of the intervenor’s interest to the filing of the motion to intervene, 

the extent of prejudice to existing parties from the timing of the motion, the extent of prejudice to 

the movant if leave to intervene were denied, and other special circumstances (if any exist and 

apply). Edwards, 78 F.3d at 1000. Ericsson’s Motion is timely filed.

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Cobblestone filed the original complaint in this case two months ago (on August 25, 2023). 

Ericsson’s Motion to intervene is filed close in time to the commencement of this action and to the 

time that Ericsson was on notice of its interests. See Edwards, 78 F.3d at 1000-01 (citing Fifth 

Circuit intervention cases finding that delays as long as five months or more are not unreasonable); 

Ericsson Inc. v. D-Link Sys., Inc., No. 6:10-cv-473 (E.D. Tex. May 4, 2012), Dkt. No. 205

(granting Intel’s partially opposed motion to intervene filed five months after the scheduling 

conference took place and nearly one year into the case); Sw. Bell Tel., L.P. v. Arthur Collins, Inc., 

No. 3:04-cv-669 (N.D. Tex. Jan. 28, 2005), Dkt. No. 50 (granting intervention by right where 

motion was filed before scheduling order was in place).

The timing of Ericsson’s Motion has not prejudiced any existing parties.4 Neither 

Defendant AT&T nor Plaintiff Cobblestone opposes Ericsson’s Motion. This non-opposition 

underscores the lack of prejudice to any party. Further, Cobblestone has no basis to claim prejudice 

because this proceeding is at an early stage and no significant event has taken place. Edwards, 78 

F.3d at 1001 (considering the stage of the proceeding under the timeliness inquiry); see also TiVo 

Inc. v. AT & T Inc., No. 2:09-cv-259, 2010 U.S. Dist. LEXIS 146363, at *18 (E.D. Tex. Mar. 31, 

2010) (finding no showing of “untimeliness” under Rule 24); Wal-Mart Stores, Inc. v. Tex. 

Alcoholic Bev. Comm’n, 834 F.3d 562, 565 (5th Cir. 2016) (“Because the Association sought 

intervention before discovery progressed and because it did not seek to delay or reconsider phases 

of the litigation that had already concluded, the Association’s motion was timely”). The first factor 

4 Alleged prejudice stemming from the actual intervention by Ericsson is different from the alleged 

prejudice stemming from the timing of the motion to intervene. The former alleged prejudice is 

irrelevant to the timing inquiry under Rule 24(a)(2). Edwards, 78 F.3d at 1002 (“This factor is 

concerned only with the prejudice caused by the applicants’ delay, not that prejudice which may 

result if intervention is allowed.”).

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thus weighs heavily in favor of allowing Ericsson’s intervention to defend allegations of 

infringement with respect to Ericsson base stations.

2. Ericsson Has a Significant Interest in the Property and 

Transactions at Issue in This Lawsuit.

A party is entitled to intervene in an action when it has “a direct, substantial, legally 

protectable interest in the proceedings.” Texas, 805 F.3d at 657 (internal quotations omitted); see 

also Glickman, 256 F.3d at 376 (quoting cases). Ericsson has such an interest in this action because 

Ericsson manufactures, develops, and distributes key network equipment and/or software of the 

type that Cobblestone alleges infringe the patents asserted in this case when deployed and used in 

AT&T’s networks. As the developer, manufacturer and distributor of accused technology, 

Ericsson has an interest in defending its technology and in clarifying the intellectual property rights 

that apply to such technology. See, e.g., Team Worldwide Corp. v. Wal-Mart Stores, Inc., No. 2:17-

cv-00235-JRG, 2017 U.S. Dist. LEXIS 201769, at *13 (E.D. Tex. Dec. 7, 2017) (finding an 

intervening manufacturer had an interest in “the ongoing sale and distribution of their products 

[which] is put at risk by [the Plaintiff’s] allegations of infringement.”); see Intellectual Ventures I 

LLC v. AT&T Mobility LLC, No. 12-193-LPS, 2014 U.S. Dist. LEXIS 125280, at *13 (D. Del. 

Sept. 8, 2014) (Stark, J.) (“[In a patent infringement suit,] intervention is necessary to enable 

Intervenors to protect their interest in products which Intervenors manufacture for Defendants, an 

interest put at risk by the litigation as Plaintiffs accuse these products of infringement.”). Overall, 

Ericsson’s interest in the issues to be litigated in this case—such as claim interpretation, validity, 

infringement, damages—is direct, substantial, and legally protectable.

3. Ericsson’s Ability to Protect Its Interests Will Be Impaired if It 

Cannot Intervene.

Ericsson would be severely prejudiced if intervention were denied. An adverse ruling of 

infringement could affect Ericsson and its relationship with its customer AT&T. See Katz v. Lear 

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8

Siegler, Inc., 909 F.2d 1459, 1464 (Fed. Cir. 1990) (“[I]t is a simple fact of life that a manufacturer 

must protect its customers, either as a matter of contract, or good business, or in order to avoid the 

damaging impact of an adverse ruling against its products.”) (quoting Codex Corp. v. Milgo

Electronic Corp., 553 F.2d 735, 737-38 USPQ 49 (1st Cir.), cert. denied, 434 U.S. 860, 54 L. Ed. 

2d 133, 98 S. Ct. 185 (1977)). Further, an adverse ruling could potentially affect Ericsson’s

reputation, its relationship with its other customers and its customer base. See Team Worldwide, 

2017 U.S. Dist. LEXIS 201769, at *13 (“[A]dverse rulings could impact each proposed 

intervenor’s relationships with other retail customers.”). Ericsson must be allowed to eliminate the 

cloud of uncertainty that Cobblestone has cast over Ericsson’s base station equipment, software 

and technology.

Moreover, an adverse decision could create precedent that could be used in other 

circumstances or proceedings against Ericsson or its other customers. This potential “stare decisis 

effect of an adverse judgment constitutes a sufficient impairment to compel intervention.” Heaton 

v. Monogram Credit Card Bank of Ga., 297 F.3d 416, 424 (5th Cir. 2002) (quoting Sierra Club v. 

Glickman, 82 F.3d 106, 109-10 (5th Cir. 1996). 

4. AT&T Cannot Adequately Represent Ericsson’s Interests in 

Defending Against Cobblestone’s Infringement Allegations.

In the Fifth Circuit, a movant satisfies the requirement of showing inadequate 

representation if it demonstrates that the defense of the case by the existing parties may be 

inadequate to protect its interests. Texas, 805 F.3d at 661. The burden to satisfy this requirement 

has been described as “minimal,” but not so minimal as to eliminate it. Id.

Although AT&T also seeks to defeat Cobblestone’s allegations, Ericsson has interests to 

defend allegations of infringement with respect to Ericsson base stations above and beyond those 

that it shares with AT&T. See Heaton, 297 F.3d at 422, 425 (reversing a district court’s denial of 

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9

a motion to intervene and noting the intervenor had met its burden because “the [intervenor’s] 

interests and [the defendant’s interests] may diverge in the future, even though, at this moment 

they appear to share common ground”). For example, AT&T may be satisfied with indemnity 

rather than a finding of non-infringement. Sw. Bell Tel., L.P., No. 3:04-cv-00669, Dkt. No. 50 at 5 

(finding under the inadequate representation inquiry that manufacturer of cell phone equipment 

should be allowed to intervene because “[the original defendant], as a customer, may be satisfied 

with indemnity rather than a finding of noninfringement”). As a result, Ericsson is motivated to 

defend its interests from Cobblestone’s claims with respect to Ericsson base stations.

Ericsson also possesses a broad and deep understanding of its equipment and technology. 

Accordingly, it is the most important source of information about its equipment and is likely the 

keeper of potentially key, relevant documents. It would be unfair to force AT&T to litigate the 

issues that Ericsson best understands. Id. (finding under the inadequate representation inquiry that 

“the customer would not be the best source for providing the detailed information about the 

[intervenor-manufacturer’s] products”). Intervention promotes both fairness and judicial economy.

As a result, Ericsson is best suited to defend its interests from Cobblestone’s claims with respect 

to Ericsson base stations.

Because Ericsson satisfies the Fifth Circuit’s four-part test for interventions of right under 

Rule 24(a), the Court should grant Ericsson’s Motion as a matter of right.

B. IN THE ALTERNATIVE, ERICSSON SHOULD BE PERMITTED 

TO INTERVENE PERMISSIVELY.

Ericsson alternatively requests the permission of the Court to intervene under Federal Rule 

of Civil Procedure 24(b), which permits a party to intervene if it “has a claim or defense that shares 

with the main action a common question of law or fact” and no undue delay or prejudice will 

result. Fed. R. Civ. P. 24(b)(1)(B); TiVo Inc., 2010 U.S. Dist. LEXIS 146363, at *18. Permissive 

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intervention presents a lower bar than intervention as a matter of right, and does not require that 

the intervenor even “have a direct personal or pecuniary interest in the subject of the litigation.” 

Newby v. Enron Corp., 443 F.3d 416, 423 (5th Cir. 2006) (quoting SEC v. U.S. Realty & 

Improvement Co., 310 U.S. 434, 459 (1940)).

For the same reasons noted above, permissive intervention for Ericsson to defend 

allegations of infringement with respect to Ericsson base stations is appropriate in this case. First, 

given that Cobblestone’s complaint appears to be directed at least in part to network equipment

and technology that Ericsson supplies to AT&T, Ericsson’s defenses will involve common 

questions of law and fact. TiVo Inc., 2010 U.S. Dist. LEXIS 146363, at *18. As noted, the issues 

to be litigated in this case—such as claim interpretation, validity, infringement, and damages—are 

common questions as to all parties. See U.S. Ethernet Innovations, LLC v. Acer, Inc., 2010 U.S. 

Dist. LEXIS 150649, at *12 (granting permissive intervention where intervenor shared common 

questions of law and fact and similar defenses as named defendant). Thus, the threshold 

requirement of Rule 24(b) is met.

Second, at this early stage in the litigation, there will be no prejudice to either AT&T or 

Cobblestone if Ericsson is permitted to intervene to defend allegations of infringement with respect 

to Ericsson products that support AT&T services. AT&T and Cobblestone do not oppose the 

motion, which underscores a lack of prejudice. Further, Ericsson does not expect any delay to 

result from its intervention to defend allegations of infringement with respect to Ericsson base 

stations. Accordingly, there will be no undue delay or prejudice.

Finally, permissive intervention is “wholly discretionary,” and in the present case, judicial 

economy weighs in favor of intervention. New Orleans Pub. Serv., Inc. v. United Gas Pipe Line 

Co., 732 F.2d 452, 471 (5th Cir. 1984). Ericsson likely possesses the relevant evidence about

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11 

certain of the accused equipment and technology it supplies to AT&T, including equipment 

specifications and testimony. Ericsson likely possesses the technical know-how. Further, 

intervention will allow Ericsson and Cobblestone to resolve the disputes in the context of the 

pending proceedings. Thus, intervention will streamline and simplify the litigation by facilitating 

discovery and promoting accurate presentation of the evidence. It would be inefficient to force 

AT&T to litigate the issues that Ericsson best understands. 

Thus, to the extent intervention is not permitted under Fed. R. Civ. P. 24(a), Ericsson

respectfully requests the Court’s permission to intervene under Rule 24(b). 

IV. CONCLUSION

For the foregoing reasons, Ericsson respectfully requests that the Court permit Ericsson to

intervene to defend allegations of infringement with respect to Ericsson base stations as a matter 

of right pursuant to Fed. R. Civ. P. 24(a)(2), or in the alternative, permissively pursuant to Fed. R. 

Civ. P. 24(b)(1)(B). 

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Dated: December 22, 2023 Respectfully Submitted,

/s/ David S. Frist 

David S. Frist (GA Bar No. 205611) 

John D. Haynes (GA Bar No. 340599) 

Emily C. Welch (GA Bar No. 606071) 

Michael C. Deane (GA Bar No. 497195) 

Sloane S. Kyrazis (GA Bar No. 878240) 

ALSTON & BIRD LLP

1201 West Peachtree Street, Suite 4900

Atlanta, GA 30309 

Phone: (404) 881-7000 

Fax: (404) 881-7777 

Email: david.frist@alston.com 

john.haynes@alston.com 

emily.welch@alston.com 

michael.deane@alston.com

sloane.kyrazis@alston.com 

Ross R. Barton (NC Bar No. 37179) 

ALSTON & BIRD LLP

101 South Tryon Street 

Suite 4000 

Charlotte, NC 28280-4000 

Telephone: (704) 444-1000 

Facsimile: (704) 444-1111 

Email: ross.barton@alston.com 

Theodore Stevenson, III (TX Bar No. 19196650) 

ALSTON & BIRD LLP

2200 Ross Avenue, Suite 2300 

Dallas TX 75201 

Phone: (214) 922-3400 

Fax: (214) 922-3899 

Email: ted.stevenson@alston.com 

Attorneys for Ericsson Inc.

Case 2:23-cv-00382-JRG-RSP Document 56 Filed 12/22/23 Page 16 of 17 PageID #: 366
CERTIFICATE OF SERVICE

The undersigned certifies that a copy of the foregoing document was served on all parties 

who have appeared in this case on December 22, 2023, via the Court’s CM/ECF system. 

Dated: December 22, 2023 /s/ David S. Frist 

David S. Frist (GA Bar No. 205611) 

ALSTON & BIRD LLP

1201 West Peachtree Street, Suite 4900

Atlanta, GA 30309 

Phone: (404) 881-7000 

Fax: (404) 881-7777 

Email: david.frist@alston.com 

CERTIFICATE OF CONFERENCE

The undersigned hereby certifies that pursuant to Local Rules CV-7(h) and (i), counsel for 

Intervenor Ericsson conferred with counsel for Defendant AT&T, as well as with counsel for 

Plaintiff Cobblestone regarding this Motion and all counsel indicated that they do not oppose the 

relief sought herein. 

Dated: December 22, 2023 /s/ David S. Frist 

David S. Frist (GA Bar No. 205611) 

ALSTON & BIRD LLP

1201 West Peachtree Street, Suite 4900

Atlanta, GA 30309 

Phone: (404) 881-7000 

Fax: (404) 881-7777 

Email: david.frist@alston.com 

Case 2:23-cv-00382-JRG-RSP Document 56 Filed 12/22/23 Page 17 of 17 PageID #: 367