New Sensations, Inc. v. Does 1-175, 947 F. Supp. 2d 146

NSI sues 88 unnamed Doe defendants identified only by IP addresses for BitTorrent-based infringements of the same NSI work; plaintiffs seek expedited discovery via Rule 45 subpoenas to ISPs to identify Doe defendants.
The alleged infringing activity involves a BitTorrent swarm where many peers share the same file; each Doe allegedly downloaded the same NSI film with a matching hash mark.
NSI alleges all Doe defendants participated in the same swarm and downloaded the same file within a narrow window, implying related transactions; geo-location data places Does within the court’s geographic area.
NSI’s forensic software traced IP addresses to swarm members; the account holder associated with an IP may not be the actual infringer, raising issues of correct defendant identification.
The court previously ordered NSI to show cause why joinder should not be severed; court will sever all Does except Doe #1 under Rule 21 and allow refiling of separate actions.
The case proceeds as part of a broader pattern of similar mass-filed actions; the court follows a sever-and-dismiss approach to protect parties and maintain judicial economy.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Is joinder proper under Rule 20(a)(2) for the Doe defendants?	NSI argues swarm-level commonality justifies joinder.	Does contend lack of same transaction/occurrence and interaction between all Doe defendants, undermining joinder.	No; joinder improper under Rule 20(a)(2) as not arising from the same transaction or occurrence.
Should the action be severed and dismissed under Rule 20(b) and 21?	Severance harms judicial economy but may be necessary for efficiency.	Severance protects fairness given individualized defenses and risk of misidentification.	Yes; interests of justice and judicial economy favor severing all Does except Doe #1 and dismissing others without prejudice.
Can NSI refile separately against each severed Doe?	Refiling preserves claims against individual infringers.	Not stated explicitly; focus on severance and dismissal.	Plaintiff may refile against each remaining Doe in separate actions.
Does the court adopt a standard beyond the traditional Rule 20 test for fairness?	Some courts used a broad fairness rationale to permit joinder.	Discretion should favor severance to avoid sprawling mass litigation.	Court uses both an objective Rule 20 analysis and a discretionary fairness approach, leading to severance.

In re EMC Corp., 677 F.3d 1351 (Fed. Cir. 2012) (logic-based 'transaction or occurrence' test for joinder limits under Rule 20(a))