Swiss intelligence puts its Josef Mengele file online after a 2071 seal failed

Switzerland's Federal Intelligence Service on Thursday published the Josef Mengele dossier that sits in the Federal Archives in Bern. The digital copy runs to about 200 pages. Passages that identify sources or private third parties are blacked out. The original file stays in the archives.

The service, known as NDB in German and SRC in French, said a historian's request for access was followed by many more. Rather than show the file on site under conditions to each applicant, it put a redacted copy on its website. It said it redacted as little as possible: names of current and former government employees tied to the service and its predecessors, protected source information, and personal data of private individuals.

The file had been scheduled for an extended protection period running to the end of 2071 under archiving law. The NDB refused access on that basis, most recently in February 2026. A complaint against that refusal showed the service was wrong to treat the dossier as sealed for that long. In May the NDB said it would reconsider. A new decision was issued on 8 September. The upload followed on Thursday.

What the pages contain

Swissinfo and the official statement describe a file built from newspaper cuttings, police reports and internal notes. Much of the press material concerns the suspicion that Mengele, the SS doctor who selected prisoners and ran medical experiments at Auschwitz, visited Switzerland more than once while he was wanted on an international warrant. Parts of the police reports are among the redactions.

Mengele left Europe after the war, lived in Argentina, Paraguay and Brazil, and died in 1979. His remains were identified in Brazil. Switzerland's interest in the file is narrower: whether a neutral state's police and intelligence services recorded his transit, and whether those records were shared or withheld.

The dossier was transferred to the Federal Archives in 2001. The NDB, as legal successor to the older services, still decides access requests. Files covered by a 2001-era decision were not flagged on the archive boxes themselves. The service said it did not know the Mengele dossier sat in that set until the requests arrived.

Why a seal to 2071 was the wrong tool

Extended protection is meant for sources who would still be at risk, or for third parties whose private lives the state has no licence to publish. Applying that seal to a man dead since 1979, and to newspaper clippings already in the public record, was the error the complaint exposed. The NDB has now chosen a public upload over a quiet reading room. Historians can download the redacted PDF. They cannot see the names the service still protects.

The file will not rewrite the Auschwitz record. It may show how Swiss services treated rumours of a wanted doctor's visits, and how long those rumours sat in a folder that no one outside the building could open. That is the information gain. A 200-page government dossier on Mengele is now a public document, with black bars where the law still requires them, because a historian asked and a complaint found the 2071 date did not apply.