Three days after the October 7 Hamas massacre in 2023, an editor on English-language Wikipedia removed most of the information about the terrorist organization's antisemitism, use of human shields and child soldiers, and human rights abuses from its main article. The material was not deleted entirely. Instead, it was moved to a separate article titled "Criticism of Hamas."
But in the days following the attack, the main Hamas article attracted nearly a million views a day, while the separate page received only a few thousand. The editor has since been banned from Wikipedia, but the changes were never subjected to a systematic review, according to a new report by the Anti-Defamation League (ADL), which argues that removing problematic editors does not necessarily undo their influence on the encyclopedia.
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Wikipedia editors have sanitized Hamas' October 7 attack that murdered more than 1,200 Israelis
(Photos: Mohammed Fayq Abu Mostafa/Reuters)
The report comes more than a year after the Jewish civil rights organization said it had identified a group of approximately 30 regular Wikipedia editors who allegedly coordinated efforts to introduce anti-Israel and antisemitic bias into articles about Israel, Jews and the Israeli-Palestinian conflict. Wikipedia's Arbitration Committee subsequently prohibited six editors from editing articles related to Israel and the Palestinians, while three others were permanently banned from the platform.
The new findings suggest that even when Wikipedia takes disciplinary action, the content left behind can continue shaping how readers understand some of the world's most contentious events.
One case examined by ADL involves the account Iskandar323, which was initially barred from editing articles about the Israeli-Palestinian conflict before being banned from Wikipedia altogether. Researchers examined the account's contributions to six major articles: "Israel," "Hamas," "Zionism," "Jews," "Gaza War" and "October 7 attacks." Of 382 edits they were able to assess, 346, approximately 91%, remained intact as of August. The figure does not establish that every surviving edit was inaccurate or biased, but it does show that the overwhelming majority remained in place after the account was banned.
In November 2023, the same account removed approximately 17,000 characters from the article about the Gaza war, including descriptions and sources documenting findings from the October 7 massacre. Among them were accounts of victims being bound with wire and burned, evidence of sexual violence and footage of an attempted beheading. Two days later, the editor removed another 7,400 characters, including testimony from soldiers and members of ZAKA, the Israeli volunteer emergency response and body recovery organization. According to ADL, the remaining text described the atrocities only as acts the terrorists had "reportedly" committed.
The report also examines the English-language article on Zionism, whose introduction continues to describe the movement as having achieved its objective "through colonization" and states that Zionists sought a state with "as few Palestinian Arabs as possible." The wording sparked a dispute among Wikipedia editors, and discussion of the language was suspended for a year in February 2025. Although the suspension has since expired, the central wording has remained.
Another account, which was not included in ADL's original investigation, edited the Zionism article 543 times, adding approximately 193,000 characters and removing about 188,000. While the article's overall length changed little, substantial portions of its content were rewritten.
Even the choice of words in the opening paragraph of Wikipedia's article about October 7 became a point of contention. One account revised the introduction to describe the attackers as having "broken out" of the blockaded Gaza Strip, while removing a reference to the first invasion of Israeli territory since 1948. Another editor reversed the change within hours.
Nevertheless, according to ADL's September review, the introduction still described the attackers' point of departure as the "blockaded" Gaza Strip. The organization cites the example to illustrate how a framing introduced through a disputed edit can survive even after the edit itself is reversed.
Most of the changes remain
(Illustration: Shutterstock)
A separate and prolonged dispute centered on the word "reportedly" in the opening of Wikipedia's article about sexual violence during the October 7 attacks. According to ADL, one account repeatedly restored the qualification over a period of 15 months, despite attempts by at least four other editors to remove it. The dispute continued even after a United Nations team concluded in March 2024 that there were reasonable grounds to believe rape and sexual violence had occurred at several locations during the attack.
Across four articles dealing with the subject and their associated discussion pages, ADL counted 9,576 edits. Accounts identified in its investigation were responsible for 832 of them and reversed other editors' contributions at least 89 times. The figures indicate substantial involvement in shaping the coverage, although they do not, by themselves, establish that every participant was acting in coordination.
The editing disputes also extended to the article covering the abduction and deaths of Shiri Bibas and her two young sons, Ariel and Kfir. In the weeks following the return of their bodies in February 2025, an editor who had not been suspended made 64 edits to the article and its discussion page. According to the report, the editor removed wording stating that the family members had been murdered, wrote that "neither Israel nor Hamas has presented evidence" supporting their respective claims, and opened a discussion titled "Evidence for claims?"
Israeli forensic authorities concluded that Shiri and her children had been murdered in captivity and found no evidence supporting Hamas' claim that they had died in an Israeli airstrike. ADL cited the editing dispute as another example of how contested language can influence the presentation of events with significant historical and emotional weight.
The report also examined whether Wikipedia's disciplinary measures had changed the behavior of the original group of editors. Comparing two six-month periods, before and after publication of its first investigation, ADL found that visible coordination had declined sharply. Discussions involving multiple members of the group on article talk pages fell by approximately 95%, while instances of editors making changes to the same articles close together in time decreased by 88%.
Overall editing activity, however, fell by only 27%, even as the group itself shrank by roughly one-third. The findings suggest that while overt collaboration became much less common, the remaining editors continued to contribute extensively.
ADL identified 19 accounts that it alleges are still promoting biased coverage: eight from the original group that had not been sanctioned and 11 others whose accounts had existed for years but were not included in the previous study. Among 229 articles edited by at least two of these accounts, one of the 11 additional editors had made the most recent edit to 144.
The organization argues that this pattern demonstrates the limitations of focusing disciplinary measures on individual editors rather than systematically examining the content they produced. Once an edit is incorporated into an article, it can remain there for years, regardless of what subsequently happens to its author.
The findings come against a backdrop of strained relations between ADL and Wikipedia's volunteer editing community. In 2024, Wikipedia editors decided to restrict the use of ADL as a source for articles concerning Israel and the Palestinians, partly over accusations that the organization conflates criticism of Israel with antisemitism. ADL continues to be generally regarded as a reliable source in other subject areas.
The Wikimedia Foundation, the nonprofit organization that operates Wikipedia, has previously emphasized that it does not determine the content of individual articles. Editorial decisions are made by Wikipedia's volunteer community, which relies on its own rules, discussion procedures and dispute-resolution mechanisms.
In its new report, ADL calls for stronger safeguards, including privately verifying the identities of editors working on sensitive subjects and restricting anonymous editing. It also urges search engines and artificial intelligence companies to disclose when their answers rely on Wikipedia and to update information in their systems when an underlying Wikipedia article is corrected.
For Wikipedia itself, the organization's principal demand is a systematic review of older contributions by editors who have been banned, with potentially problematic changes examined and corrected where necessary.
The underlying concern extends beyond individual articles or editors. Wikipedia content is widely used by search engines and AI systems, giving the wording of its entries an influence far beyond the encyclopedia's own readership. ADL argues that inaccurate or misleading material can therefore spread even after the original editing dispute has ended.
For the organization, the central lesson is that disciplinary action alone cannot guarantee the accuracy of the historical record. Wikipedia may be able to remove an editor from its platform, but the words that editor left behind can remain part of what millions of people read for years.