United States Court of Appeals 

for the Federal Circuit 

__________________________ 

IN RE EMC CORPORATION, DECHO 

CORPORATION, AND IOMEGA CORPORATION, 

Petitioners. 

__________________________ 

Miscellaneous Docket No. 100 

__________________________ 

On Petition for Writ of Mandamus to the United 

States District Court for the Eastern District of Texas in 

case no. 10-CV-435, Judge Michael H. Schneider. 

__________________________ 

ON PETITION FOR WRIT OF MANDAMUS 

__________________________ 

CHRIS R. OTTENWELLER, Orrick, Herrington & Sutcliffe LLP, of Menlo Park, California, for petitioners. 

With him on the petition were I. NEEL CHATTERJEE and 

DEREK F. KNERR; and MARK S. DAVIES, RACHEL M.

MCKENZIE and KATHERINE M. KOPP, of Washington, DC. 

Of counsel on the petition were PAUL T. DACIER, 

KRISHNENDU GUPTA and WILLIAM R. CLARK, EMC Corporation, of Hopkinton, Massachusetts. 

MATTHEW B. LOWRIE, Foley & Lardner LLP, of Boston, 

Massachusetts, for Carbonite, Inc. With him on the brief 

were KEVIN M. LITTMAN; and GEORGE C. BECK, of Washington, DC. 
2 IN RE EMC CORPORATION

BRIAN W. LACORTE, Ballard Spahr LLP, of Phoenix, 

Arizona, for GoDaddy.com, Inc. 

SHAMITA D. ETIENNE-CUMMINGS, White & Case LLP, 

of Washington, DC, for Iron Mountain Incorporated, et al. 

With her on the brief was BIJAL V. VAKIL, of Palo Alto, 

California. 

FREDERICK S. BERRETTA, Knobbe, Martens, Olson & 

Bear, LLP, of San Diego, California, for Pro Softnet 

Corporation. 

JOHN M. DESMARAIS, Desmarais LLP, of New York, 

New York, for respondent Oasis Research, LLC. With 

him on the response were ALAN S. KELLMAN and TAMIR 

PACKIN. 

MATTHEW D. MCGIL, Gibson, Dunn & Crutcher LLP, 

of Washington, DC, for amici curiae Cisco Systems, Inc. et 

al. With him on the brief was JOHN F. BASH. Also on the 

brief was ELIZABETH ROGERS BRANNEN, Oracle Legal, of 

Redwood Shores, California, for amicus curiae Oracle 

Corporation. 

__________________________ 

Before RADER, Chief Judge, DYK and MOORE, Circuit 

Judges. 

DYK, Circuit Judge. 

ORDER 

Petitioners EMC Corp., Decho Corp., and Iomega 

Corp. (collectively, “EMC”) seek a writ of mandamus to 

direct the United States District Court for the Eastern 

District of Texas to sever and transfer the claims against 

them to the United States District Court for the District 

of Utah. Petitioners Carbonite Inc. (“Carbonite”), Iron 
IN RE EMC CORPORATION 3 

Mountain Inc. and Iron Mountain Information Management, Inc. (collectively, “Iron Mountain”), GoDaddy.com, 

Inc. (“GoDaddy”), and Pro Softnet Corp. (“Pro Softnet”) 

join in EMC’s petition, seeking to have the claims against 

them severed and transferred to federal district courts in 

Massachusetts, Arizona, and California. We grant the 

petition in part and direct the district court to determine 

whether the claims “aris[e] out of the same transaction, 

occurrence, or series of transactions or occurrences,” Fed. 

R. Civ. P. 20(a), under the correct legal standard. 

I 

Petitioners are eight of eighteen companies named as 

defendants in a single complaint filed by Oasis Research 

LLC (“Oasis”) in the Eastern District of Texas. Oasis 

asserted the method claims from four patents, U.S. Patent 

Nos. 5,771,354; 5,901,228; 6,411,943; and 7,080,051 (claim 

9 only), all of which deal with off-site computer data 

storage. Specifically, the patents claim methods for 

allowing home computer users to remotely connect to an 

online service system for purposes of external data and 

program storage and additional processing capacities in 

exchange for a fee. 

The defendants in this case are all alleged to offer 

services that provide online backup and storage for home 

or business computer users. See Complaint at 7-12, Oasis 

Research, LLC v. ADrive LLC, No. 4:10-cv-435 (E.D. Tex. 

Aug. 30, 2010), ECF No. 1. In particular, petitioners are 

alleged to offer online backup and storage through websites such as www.mozy.com and www.atmosonline.com 

(EMC); www.carbonite.com (Carbonite); 

backup.ironmountain.com (Iron Mountain); 

www.godaddy.com/gdshop/email/vsdb_landing.asp (GoDaddy); and www.idrive.com (Pro Softnet). Id. at 8, 9, 11, 

12. 
4 IN RE EMC CORPORATION

Petitioners sought orders to sever and transfer the 

claims against them to more appropriate venues, arguing 

that because there was no concert of action, the claims 

against them did not arise out of the same transaction or 

occurrence, as required by Rule 20 of the Federal Rules of 

Civil Procedure. Oasis argued that although the asserted 

“patents cover a broad range of technologies, the accused 

infringement in this case is limited to online 

backup/storage services,” and that “each defendant offers 

a similar commercial online backup/storage service” such 

that “[t]he steps taken to provide those services are 

covered by the asserted method claims of the patents-insuit.” Plaintiff Oasis Research, LLC’s Opposition to 

Defendants’ Venue and Jurisdiction Related Motions at 1, 

Oasis Research, LLC v. ADrive LLC, No. 4:10-cv-435 (E.D. 

Tex. Dec. 3, 2010), ECF No. 133. 

The magistrate judge found nothing improper about 

maintaining these claims in one action in the Eastern 

District of Texas, for “[c]laim validity, claim construction, 

and the scope of the four patents . . . are questions common to all Defendants in this case.” Oasis Research, LLC 

v. ADrive, LLC, No. 4:10-CV-435, 2011 WL 3099885, at *3 

(E.D. Tex. May 23, 2011). Moreover, the claims “ar[ose] 

out of the same transaction, occurrence, or series of transactions or occurrences,” according to the magistrate judge, 

because the accused services were “not dramatically 

different.” Id. at *2. Finally, the magistrate judge stated 

that “granting Defendants’ motions to sever and transfer 

would be the division of a single action into seven different lawsuits scattered across the country.” Id. at *4. The 

district court adopted these findings and conclusions. 

Oasis Research, LLC v. ADrive, LLC, No. 4:10-CV-435, 

2011 WL 3103972 (E.D. Tex. July 25, 2011). 
IN RE EMC CORPORATION 5 

II 

A 

We first turn our attention to this court’s jurisdiction. 

The remedy of mandamus is available in extraordinary 

situations “to correct a clear abuse of discretion or usurpation of judicial power.” In re Calmar, Inc., 854 F.2d 

461, 464 (Fed. Cir. 1988). A party seeking a writ bears 

the burden of proving that it has no other means of obtaining the relief desired, see Mallard v. U.S. Dist. Court, 

490 U.S. 296, 309 (1989), and that the right to issuance of 

the writ is “clear and indisputable,” Allied Chem. Corp. v. 

Daiflon, Inc., 449 U.S. 33, 35 (1980) (per curiam). 

It is well established that mandamus is available to 

contest a patently erroneous error in an order denying 

transfer of venue. See In re Apple, Inc., 602 F.3d 909 (8th 

Cir. 2010); In re Nintendo Co., 589 F.3d 1194 (Fed. Cir. 

2009); In re Hoffmann-La Roche Inc., 587 F.3d 1333 (Fed. 

Cir. 2009); In re Genentech, Inc., 566 F.3d 1338 (Fed. Cir. 

2009); In re TS Tech USA Corp., 551 F.3d 1315 (Fed. Cir. 

2008); In re Volkswagen of Am., Inc., 545 F.3d 304 (5th 

Cir. 2008) (en banc). 

We must here address as a matter of first impression 

whether mandamus can be an appropriate means to test a 

district court’s discretion in ruling on motions to sever 

and transfer. While transfer motions are governed by 

regional circuit law, see In re Link_A_Media Devices 

Corp., 662 F.3d 1221, 1222-23 (Fed. Cir. 2011), motions to 

sever are governed by Federal Circuit law because joinder 

in patent cases is based on an analysis of the accused acts 

of infringement, and this issue involves substantive issues 

unique to patent law. We thus apply Federal Circuit law 

to determine the availability of mandamus, and to the 

underlying issue of whether the motion to sever should be 

granted. In other comparable circumstances we have 
6 IN RE EMC CORPORATION

applied Federal Circuit law. See, e.g., Manildra Milling 

Corp. v. Ogilvie Mills, Inc., 76 F.3d 1178, 1182 (Fed. Cir. 

1996) (meaning of “prevailing party”); Reebok Int’l Ltd. v. 

J. Baker, Inc., 32 F.3d 1552, 1555 (Fed. Cir. 1994) (preliminary injunctions); Beverly Hills Fan Co. v. Royal 

Sovereign Corp., 21 F.3d 1558, 1564-65 (Fed. Cir. 1994) 

(personal jurisdiction). Application of our law is particularly appropriate since, as discussed below, Congress has 

recently adopted a special statute governing joinder in 

patent cases. Nonetheless, in developing our own law, we 

frequently look to the law of our sister circuits for guidance. See, e.g., Beverly Hills Fan, 21 F.3d at 1566-68. 

We conclude that mandamus is available as a remedy. With regard to the “no other means” requirement, 

there is no meaningful distinction between a petitioner’s 

seeking review of an order denying transfer because the 

district court clearly abused its discretion in applying the 

§ 1404(a) factors and a petitioner’s seeking review of an 

order denying a motion to transfer because the district 

court clearly abused its discretion by not severing the 

claim as a predicate to determining whether to transfer. 

In either case, a defendant would not have an adequate 

remedy for an improper failure to transfer or sever the 

case by way of an appeal from an adverse final judgment 

because the defendant would be unable to demonstrate 

“that it would have won the case had it been tried in a 

convenient [venue].” In re Volkswagen, 545 F.3d at 319 

(alteration in original) (quoting In re Nat’l Presto Indus., 

Inc., 347 F.3d 662, 663 (7th Cir. 2003)). 

Nor does the “clear and indisputable” requirement 

preclude us from issuing the writ. To be sure, Rule 21, 

which authorizes a district court to “sever any claim 

against a party,” provides a district court broad discretion. Fed. R. Civ. P. 21. Just as when weighing the 

§ 1404(a) factors, however, that discretion must be exercised within the boundaries set by relevant statutes and 
IN RE EMC CORPORATION 7 

precedent. See In re Volkswagen, 545 F.3d at 310. A 

district court abuses its discretion if it relies on an erroneous conclusion of law. Id. On mandamus review, we 

review for these types of errors, but we will only grant 

mandamus relief in extraordinary circumstances. Id. 

Here, if joinder was improper, the petitioners will not 

have a meaningful opportunity to present individualized 

defenses on issues such as infringement, willfulness, and 

damages because each defendant will have limited opportunities to present its own defense to the jury. We note 

that district courts have expressed similar concerns. See, 

e.g., WiAV Networks, LLC v. 3Com Corp., No. C 10-03448, 

2010 WL 3895047, at *2 (N.D. Cal. Oct. 1, 2010) (“Each 

defendant has simply been thrown into a mass pit with 

others to suit plaintiff’s convenience. In this connection, 

the accused defendants—who will surely have competing 

interests and strategies—are also entitled to present 

individualized assaults on questions of non-infringement, 

invalidity, and claim construction.”). 

In an analogous case, the Fifth Circuit in In re Fibreboard Corp., 893 F.2d 706, 712 (5th Cir. 1990), granted 

mandamus to undo joinder based on procedural fairness 

concerns in a “mass tort” action when it was not established that “the questions of law or fact common to the 

members of the class predominate over any questions 

affecting individual members” as required by Rule 

23(b)(3). The procedural safeguards pertaining to class 

certification do not apply here. But Rule 20’s requirements are designed to prevent similar unfairness. Like 

the requirements of Rule 23 in class actions, Rule 20’s two 

requirements—that the claims share “question[s] of law 

or fact common to all defendants,” and “aris[e] out of the 

same transaction [or] occurrence”—help ensure that the 

scope of the action remains “consistent with fairness to 

the parties.” United Mine Workers of Am. v. Gibbs, 383 

U.S. 715, 724 (1966). 
8 IN RE EMC CORPORATION

B 

We turn to the issue of severance. We first note the 

unusual circumstances from which this petition comes 

before us. Recently, Congress addressed the issue of 

joinder in patent cases in section 19 of the Leahy-Smith 

America Invents Act, which was signed into law just days 

after this petition was filed. See Leahy-Smith America 

Invents Act, Pub. L. No. 112-29, sec. 19(d), § 299, 125 

Stat. 284, 332-33 (2011) (to be codified at 35 U.S.C. § 299) 

(providing in relevant part that accused infringers may be 

joined in one action as defendants or have their actions 

consolidated for trial only if the allegations of infringement “aris[e] out of the same transaction, occurrence, or 

series of transactions or occurrences relating to the making, using, importing into the United States, offering for 

sale, or selling of the same accused product or process”). 

While petitioners argue that joinder here would be 

improper under the new and old rules, they wisely refrain 

from arguing that the new 35 U.S.C. § 299 itself mandates this outcome. As a general rule, we do not give 

statutes retroactive effect “unless Congress clearly indicates its intention to do so.” Lowder v. Dep’t of Homeland 

Sec., 504 F.3d 1378, 1384 (Fed. Cir. 2007). This new 

provision is not retroactive, applying only “to any civil 

action commenced on or after the date of the enactment of 

th[e] Act.” Leahy-Smith America Invents Act § 19(e), 125 

Stat. at 333. The timing of this petition means that our 

decision will only govern a number of cases that were filed 

before the passage of the new joinder provision. 

When considering a motion to sever under Rule 21, 

“courts have looked to Rule 20 for guidance.” Acevedo v. 

Allsup’s Convenience Stores, Inc., 600 F.3d 516, 521 (5th 

Cir. 2010); see also Coughlin v. Rogers, 130 F.3d 1348, 

1351 (9th Cir. 1997) (applying the requirements of Rule 

20 to a motion to sever under Rule 21). Defendants may 
IN RE EMC CORPORATION 9 

be joined in a single action only if the two independent 

requirements of Rule 20 are satisfied: (1) the claims 

against them must be asserted “with respect to or arising 

out of the same transaction, occurrence, or series of transactions or occurrences,” and (2) there must be a “question 

of law or fact common to all defendants.” Fed. R. Civ. P. 

20(a)(2). Rule 20 clearly contemplates joinder of claims 

arising from a “series of transactions or occurrences”—a 

single transaction is not required. 

It is clear that where defendants are alleged to be 

jointly liable, they may be joined under Rule 20 because 

the transaction-or-occurrence test is always satisfied. See 

Temple v. Synthes Corp., 498 U.S. 5, 7 (1990) (per curium) 

(noting that a joint tortfeasor is a permissive party). But 

the language of Rule 20 makes clear that joinder is not 

limited to such situations. Defendants may be joined if 

“any right to relief is asserted against them jointly, severally, or in the alternative,” Fed. R. Civ. P. 20(a)(2), so an 

allegation of joint liability is not required. 

The cases make equally clear that the fact that the 

defendants are independent actors does not preclude 

joinder as long as their actions are part of the “same 

transaction, occurrence, or series of transactions or occurrences.” The decision of the Supreme Court in United 

States v. Mississippi, 380 U.S. 128 (1965), provides substantial guidance. In that case, the United States sued 

Mississippi, three election commissioners, and six county 

voting registrars, alleging that the defendants were acting 

to deny the right of black citizens to vote. Id. at 130. Five 

of the voting registrars moved for severance, and the 

district court held that they could not be sued jointly. Id.

at 131. The Supreme Court, however, held that joinder 

was proper under Rule 20 because the registrars were 

engaged in a “series of transactions or occurrences.” Id. at 

142-43. 
10 IN RE EMC CORPORATION

The permissibility of joining defendants who act independently is also clear from the origins of Rule 20. The 

advisory committee notes specifically state that Rule 

20(a)(2), concerning joinder of defendants, “is derived 

from English Rules Under the Judicature Act (The Annual 

Practice, 1937) O. 16, r. 4,” which was the English rule for 

joinder of defendants. Fed. R. Civ. P. 20 advisory committee note. The referenced 1937 edition of The Annual 

Practice explains that before the revision of the English 

joinder rules, “it was held that claims for damages against 

two or more defendants in respect of their several liability 

for separate torts could not be combined in one action.” 

W. Valentine Ball et al., The Annual Practice 240 (55th 

ed. 1937) (citing Sadler v. G. W. Ry. Co., [1896] A.C. 450 

(H.L.)). The joinder rule for plaintiffs (O. 16, r. 1) was 

then revised in 1896 to allow joinder of claims “in respect 

of or arising out of the same transaction or series of 

transactions.” Id. at 213. The courts held that this 

change also required a revised interpretation of the 

joinder rule for defendants. Id. at 240. As The Annual 

Practice stated, under the revised rule, “claims in respect 

of separate torts may be joined.” Id. at 241.1

 

1 To determine when claims against different alleged patent infringers do satisfy the transaction-oroccurrence prong of Rule 20, it is appropriate to look at 

joinder of defendants in other tort cases because “[p]atent 

infringement is a tort.” Wordtech Sys., Inc. v. Integrated 

Network Solutions, Inc., 609 F.3d 1308, 1313 (Fed. Cir. 

2010) (quoting Mars, Inc. v. Coin Acceptors, Inc., 527 F.3d 

1359, 1365 (Fed. Cir. 2008)); see also Carbice Corp. of Am. 

v. Am. Patents Dev. Corp., 283 U.S. 27, 33 (1931) (“Infringement, whether direct or contributory, is essentially 

a tort, and implies invasion of some right of the patentee.”). 
IN RE EMC CORPORATION 11

Based on this history, it follows that the mere fact 

that a case involves independent actors as defendants 

does not necessarily bring the case outside the scope of 

Rule 20. The question then is under what circumstances 

is the joinder of independent actors permissible under 

Rule 20. 

In imposing both the transaction-or-occurrence requirement and the requirement of a common question of 

law or fact, Rule 20 makes clear that the existence of a 

single common question of law or fact alone is insufficient 

to satisfy the transaction-or-occurrence requirement. In 

the present context the mere fact that infringement of the 

same claims of the same patent is alleged does not support joinder, even though the claims would raise common 

questions of claim construction and patent invalidity. 

District courts outside the Eastern District of Texas have 

generally agreed in cases involving patent, copyright, and 

trademark law.2 So too we have previously held that 

 2 See, e.g., Rudd v. Lux Prods. Corp. Emerson Climate Techs. Braeburn Sys., No. 09-CV-6957, 2011 WL 

148052, at *3 (N.D. Ill. Jan. 12, 2011) (“After researching 

the issue, the Court determines that [the Eastern District 

of Texas’s] approach [to Rule 20] is in the minority.”); 

WiAV Networks, LLC, 2010 WL 3895047, at *2 

(“[N]umerous courts have found that ‘joinder is often 

improper where [multiple] competing businesses have 

allegedly infringed the same patent by selling different 

products.’” (second alteration in original)); Golden Scorpio 

Corp. v. Steel Horse Bar & Grill, 596 F. Supp. 2d 1282, 

1285 (D. Ariz. 2009) (holding that defendants who independently infringed the same trademark are not part of 

the same transaction or occurrence); Arista Records LLC 

v. Does 1-4, 589 F. Supp. 2d 151, 154-55 (D. Conn. 2008) 

(holding that defendants who independently infringed the 

same copyright are not part of the same transaction or 

occurrence). 
12 IN RE EMC CORPORATION

claims of infringement of the same patent by independent 

parties, without more, are not part of the same transaction or occurrence for purposes of Rules 13 and 14, and 

are instead “new claims against new parties . . . not 

authorized by the joinder rules.” Frank’s Casing Crew & 

Rental Tools, Inc. v. PMR Techs., Ltd., 292 F.3d 1363, 

1372 (Fed. Cir. 2002). Even though the new claims in 

Frank’s Casing “were based on infringement of the same 

patent,” they did not arise out of the same transaction or 

occurrence because the factual overlap was insufficient. 

Id. at 1372 n.6. 

As other courts have noted, the transaction-oroccurrence test of Rule 20(a) is similar to the transactionor-occurrence test of Rule 13(a) for compulsory counterclaims, which has been construed as requiring a “logical 

relationship” between the claims. See Moore v. N.Y. 

Cotton Exch., 270 U.S. 593, 610 (1926) (noting that 

“‘[t]ransaction’ is a word of flexible meaning” and holding 

that two claims arise from the same “transaction” when 

there is a “logical relationship” between them); Mosley v. 

Gen. Motors Corp., 497 F.2d 1330, 1333 (8th Cir. 1974) 

(holding, based on analogy to Rule 13(a), that the “transaction or occurrence” requirement of Rule 20 permits “all 

reasonably related claims” to be tried together); see also

Alexander v. Fulton Cnty., 207 F.3d 1303, 1323 (11th Cir. 

2000) (same), overruled on other grounds by Manders v. 

Lee, 338 F.3d 1304 (11th Cir. 2003) (en banc). 

Professors Wright and Miller concluded that “[t]he 

logical-relationship test employed under Rule 13(a) seems 

consistent with the philosophy underlying the passage in 

Rule 20 that allows joinder of parties whenever the claims 

arise out of ‘the same series of transactions or occurrences.’” 7 Charles Alan Wright et al., Federal Practice 

and Procedure § 1653 (3d ed. 2001). Courts have applied 

this “transaction or occurrence” requirement using a 

“case-by-case approach” based on a “flexib[le] . . . standard 
IN RE EMC CORPORATION 13

[that] enables the federal courts to promote judicial 

economy by permitting all reasonably related claims for 

relief by or against different parties to be tried in a single 

proceeding under the provisions of Rule 20.” Id. The 

Supreme Court has stated that under the Federal Rules 

of Civil Procedure, “the impulse is toward entertaining 

the broadest possible scope of action consistent with 

fairness to the parties; joinder of claims, parties and 

remedies is strongly encouraged.” Gibbs, 383 U.S. at 724. 

Thus, independent defendants satisfy the transactionor-occurrence test of Rule 20 when there is a logical 

relationship between the separate causes of action. The 

logical relationship test is satisfied if there is substantial 

evidentiary overlap in the facts giving rise to the cause of 

action against each defendant. In other words, the defendants’ allegedly infringing acts, which give rise to the 

individual claims of infringement, must share an aggregate of operative facts. The Supreme Court in United 

States v. Mississippi, 380 U.S. at 142-43, adopted this 

approach, as have several of our sister circuits. For 

example, in Coughlin v. Rogers, 130 F.3d at 1350, the 

Ninth Circuit stated that the “same transaction” requirement of Rule 20 “refers to similarity in the factual background of a claim.” And in the Fifth Circuit, “[w]hile 

using the ‘logical relationship’ concept, [the] Circuit gives 

weight to whether the claim and counterclaim share an 

‘aggregate of operative facts.’” N.Y. Life Ins. Co. v. Deshotel, 142 F.3d 873, 882 (5th Cir. 1998) (quoting McDaniel v. 

Anheuser-Busch, Inc., 987 F.2d 298, 304 (5th Cir. 1993)). 

The First Circuit has also adopted this “aggregate of 

operative facts” approach. See Iglesias v. Mut. Life Ins. 

Co., 156 F.3d 237, 242 (1st Cir. 1998), abrogated on other 

grounds by Global NAPs, Inc. v. Verizon New Eng. Inc., 

603 F.3d 71, 86 n.18 (1st Cir. 2010). Similarly, in Tank 

Insulation International, Inc. v. Insultherm, Inc., the Fifth 

Circuit evaluated whether two claims satisfy the transaction-or-occurrence test by considering, among other 
14 IN RE EMC CORPORATION

things, whether the issues of fact and law “largely are the 

same” and “whether substantially the same evidence” will 

support or refute the claims. 104 F.3d 83, 85-56 (5th Cir. 

1997) (quoting Park Club, Inc. v. Resolution Trust Corp., 

967 F.2d 1053, 1058 (5th Cir. 1992)). 

We think the “not dramatically different” standard 

used by the district court is inconsistent with these authorities. That standard seems to require little more than 

the existence of some similarity in the allegedly infringing 

products or processes, similarity which would exist simply 

because the same patent claims are alleged to be infringed. See Oasis Research, 2011 WL 3099885, at *2 

(stating that “each Defendant offers an online 

backup/storage service to its customers that allegedly 

infringes Plaintiff’s patents” and that “the Court finds 

this is sufficient to satisfy the first prong under Rule 20”). 

Where different products or processes were accused of 

infringing the same claims, the “not dramatically different” standard would inevitably be satisfied. The petitioners here point out the difficulties that would be presented 

by joinder of claims involving “different” products or 

processes, see, e.g., EMC Br. at 9-10 (noting “the prejudice 

and potential confusion of being forced to defend claims 

alongside unrelated parties with different products or 

services and possibly different strategies”), and point to 

cases outside the Eastern District of Texas that have 

refused joinder where the products or processes are 

“different.”3 

 3 See, e.g., EIT Holdings LLC v. Yelp!, Inc., No. C 

10-05623, 2011 WL 2192820, at *2 (N.D. Cal. May 12, 

2011) (finding joinder improper where defendants’ “websites implement different functionalities, through different software, that works in different ways”); Sorensen v. 

DMS Holdings, Inc., No. 08-cv-559, 2010 WL 4909615, at 

*1 (S.D. Cal. Nov. 24, 2010) (“[A]lleging a common manu-
IN RE EMC CORPORATION 15

We agree that joinder is not appropriate where different products or processes are involved. Joinder of independent defendants is only appropriate where the accused 

products or processes are the same in respects relevant to 

the patent. But the sameness of the accused products or 

processes is not sufficient. Claims against independent 

defendants (i.e., situations in which the defendants are 

not acting in concert) cannot be joined under Rule 20’s 

transaction-or-occurrence test unless the facts underlying 

the claim of infringement asserted against each defendant 

share an aggregate of operative facts. To be part of the 

“same transaction” requires shared, overlapping facts that 

give rise to each cause of action, and not just distinct, 

albeit coincidentally identical, facts. The sameness of the 

accused products is not enough to establish that claims of 

infringement arise from the “same transaction.” Unless 

there is an actual link between the facts underlying each 

claim of infringement, independently developed products 

using differently sourced parts are not part of the same 

transaction, even if they are otherwise coincidentally 

identical. 

 

facturer and infringement of the same patent is not 

enough to support joinder where defendants are unrelated 

companies, selling different products.”); Children’s Network, LLC v. PixFusion LLC, 722 F. Supp. 2d 404, 415 

(S.D.N.Y. 2010) (“Joinder of unrelated parties into one 

action is generally inappropriate where, as here, the 

infringement of the same patent is alleged, but the products are different.”); N.J. Mach. Inc. v. Alford Indus., Inc., 

No. 89-1879, 1991 WL 340196, at *2 (D.N.J. Oct. 7, 1991) 

(finding joinder of “claims of infringement against unrelated defendants, involving different machines” improper 

where “the plaintiff fails to adequately allege or support 

any connection or substantial similarity between the 

machines of the proposed defendants”). 
16 IN RE EMC CORPORATION

In addition to finding that the same product or process is involved, to determine whether the joinder test is 

satisfied, pertinent factual considerations include whether 

the alleged acts of infringement occurred during the same 

time period, the existence of some relationship among the 

defendants, the use of identically sourced components, 

licensing or technology agreements between the defendants, overlap of the products’ or processes’ development 

and manufacture, and whether the case involves a claim 

for lost profits. The district court enjoys considerable 

discretion in weighing the relevant factors.4

In exercising its discretion, the district court should 

keep in mind that even if joinder is not permitted under 

Rule 20, the district court has considerable discretion to 

consolidate cases for discovery and for trial under Rule 42 

where venue is proper and there is only “a common question of law or fact.” Fed. R. Civ. P. 42(a); see 9A Wright et 

al., supra, § 2382 (“[T]he existence of a common question 

by itself is enough to permit consolidation under Rule 

42(a), even if the claims arise out of independent transactions.”). Common pretrial issues of claim construction 

and patent invalidity may also be adjudicated together 

through the multidistrict litigation procedures of 28 

U.S.C. § 1407. See, e.g., In re Cruciferous Sprout Litig., 

 

4 As discussed above, we do not decide today 

whether the new joinder provision at 35 U.S.C. § 299 

changes the test for joinder of defendants in patent infringement actions, and our approach to the new provision 

is not dictated by this case. The new statue only allows 

joinder of independent defendants whose acts of infringement involve “the same accused product or process.” Id.

§ 299(a)(1) (emphasis added). We need not decide 

whether the sameness test in the new legislation is identical to the sameness test we adopt here for cases not 

covered by the new legislation. 
IN RE EMC CORPORATION 17

301 F.3d 1343 (Fed. Cir. 2002) (affirming grant of summary judgment of patent invalidity in consolidated cases 

involving the same three patents). On the other hand, 

even if a plaintiff’s claims arise out of the same transaction and there are questions of law and fact common to all 

defendants, “district courts have the discretion to refuse 

joinder in the interest of avoiding prejudice and delay, 

ensuring judicial economy, or safeguarding principles of 

fundamental fairness.” Acevedo, 600 F.3d at 521 (citations omitted). In a complicated patent litigation a large 

number of defendants might prove unwieldy, and a district court would be justified in exercising its discretion to 

deny joinder “when different witnesses and documentary 

proof would be required.” Id. at 522. 

C 

Since the district court here applied an incorrect test, 

the district court’s ruling must be set aside, and the 

issues of severance and joinder considered under the 

proper standard. We therefore grant the petition to the 

limited extent that we vacate the district court’s order 

denying the motions to sever and transfer, and direct the 

district court to reconsider those motions in light of the 

correct test. 

Accordingly, 

IT IS ORDERED THAT: 

(1) The petition for a writ of mandamus is granted. 

(2) Carbonite, Iron Mountain, GoDaddy, and Pro 

Softnet’s motions to join EMC’s petition are also granted 

to the extent that the district court is directed to reconsider their motions in light of the correct test. 
18 IN RE EMC CORPORATION

 FOR THE COURT

 May 4, 2012 /s/ Jan Horbaly 

 Date Jan Horbaly 

 Clerk