(Slip Opinion)
OCTOBER TERM, 2022
1
Syllabus
NOTE: Where it is feasible, a syllabus (headnote) will be released, as is
being done in connection with this case, at the time the opinion is issued.
The syllabus constitutes no part of the opinion of the Court but has been
prepared by the Reporter of Decisions for the convenience of the reader.
See United States v. Detroit Timber & Lumber Co., 200 U. S. 321, 337.
SUPREME COURT OF THE UNITED STATES
Syllabus
TWITTER, INC. v. TAAMNEH ET AL.
CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR
THE NINTH CIRCUIT
No. 21–1496. Argued February 22, 2023—Decided May 18, 2023
In 2017, Abdulkadir Masharipov carried out a terrorist attack on the
Reina nightclub in Istanbul, Turkey, on behalf of the Islamic State of
Iraq and Syria (ISIS), a designated Foreign Terrorist Organization.
Masharipov killed Nawras Alassaf and 38 others. Alassaf’s family
then brought this suit under 18 U. S. C. §2333, an Antiterrorism Act
(ATA) provision that permits U. S. nationals who have been “injured
. . . by reason of an act of international terrorism” to file a civil suit for
damages. Instead of suing ISIS directly under §2333(a), the plaintiffs
(respondents here) invoked §2333(d)(2) to sue three of the largest social-media companies in the world—Facebook, Twitter (petitioner
here), and Google (which owns YouTube)—for aiding and abetting
ISIS.
The parties today agree on the basic aspects of these platforms: Billions of people from around the world have signed up for them and
upload massive amounts of content each day. Defendants profit from
that content by placing advertisements on or near it and use “recommendation” algorithms that match content, advertisements, and users
based on information about the use, advertisement, and content being
viewed. As the parties represent things, the algorithms here match
any content with any user who is more likely to view that content, and
the platforms perform little to no front-end screening on any content
before it is uploaded.
Plaintiffs, however, allege that for several years the companies have
knowingly allowed ISIS and its supporters to use their platforms and
“recommendation” algorithms as tools for recruiting, fundraising, and
spreading propaganda; plaintiffs further allege that these companies
have, in the process, profited from the advertisements placed on ISIS’
tweets, posts, and videos. The District Court dismissed the complaint