Sigurdur Ingi Thordarson, an Icelandic hacker who volunteered for WikiLeaks in 2010–2011, became an FBI informant after contacting the U.S. Embassy in Reykjavik in August 2011. He handed over terabytes of WikiLeaks material, including copied hard drives, and reportedly received $5,000 to compensate for time spent assisting investigators. In May 2019, he signed an immunity agreement with U.S. prosecutors and was identified as “Teenager” in the indictment seeking Julian Assange’s extradition. Thordarson had also pleaded guilty in Iceland to embezzlement and financial fraud, including taking about $50,000 from a WikiLeaks online store; in 2014 he was ordered to pay roughly 7 million Icelandic krona and serve two years in prison.
In a June 2021 interview with Icelandic newspaper Stundin, Thordarson said he had fabricated or misrepresented parts of earlier testimony about Assange, including claims that Assange directed him to hack or obtain recordings of Icelandic lawmakers. Deutsche Welle, The Hill, Der Spiegel and The Intercept described him as a key witness, while The Washington Post reported that his testimony was not the basis of the core charges and primarily concerned Assange’s contact with Chelsea Manning. WikiLeaks and others disputed the reporting, and a 2024 documentary alleged the recantation story was orchestrated with WikiLeaks involvement; those allegations remain contested. The episode exposed the evidentiary and credibility risks created when prosecutors rely on an incentivized informant with prior fraud convictions.
