Ludwik Rajchman's FBI surveillance file shows no further US contact with him after May 1957, corroborating but not proving that he never returned

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A 1970 Washington Field Office memo (dated 3/3/70), requesting authority to destroy decades-old surveillance records on Ludwik Rajchman, summarizes that office's file endpoint: "The last communication in WFO's file on Rajchman is the Boston report of SA Christopher H. Kokolakis, dated 5/6/57, which reports that Rajchman was a delegate to the United Nations International Children's Emergency Fund and a member of the staff of the International Children's Center in Paris, France. The report indicates that subject was living in Paris, France." No later entry in the file — through its final 1970 administrative correspondence — documents Rajchman again in the United States.

One detail in the same memo cuts against the inference rather than for it: the Washington Field Office had not been the office of origin since January 1950, when, as the memo records, "subject moved to New York City, and New York was made origin." A summary of when Washington's file went quiet is therefore a narrower fact than a summary of when the Bureau stopped hearing about him.

This bears on the claim, repeated from an uncited Wikipedia sentence in claim-ludwik-rajchman-squeezed-out-by-both-cold-war-blocs, that Rajchman "never returned to the United States" after his February 1957 subpoena (see claim-fbi-file-confirms-siss-subpoenaed-rajchman-february-1957). The FBI's silence after May 1957 is consistent with a permanent departure, but an intelligence-surveillance file falling quiet is evidence of the Bureau losing interest or jurisdiction, not a positive record of Rajchman's whereabouts every year thereafter. It does not, by itself, rule out an unrecorded later visit.