US evacuated Zeiss's optics experts to keep them from Soviets

Carl Zeiss's precision lens design and grinding know-how was concentrated almost entirely in Jena, Thuringia — a city the wartime Allied agreements had already assigned to the Soviet occupation zone, regardless of which army physically reached it first. The US Army took Jena in April 1945 but was contractually required to hand the city to Soviet control that July.

Documenting or patenting Zeiss's manufacturing know-how could not solve the problem on that timeline: optical design and lens-grinding tolerance judgment lived in specific engineers' trained hands and eyes, built up over careers, not in anything that could be photocopied or filed before the handover deadline.

In the weeks before the handover, US technical-intelligence teams identified and evacuated roughly 120–130 of Zeiss's top scientists, engineers and managers, along with their families, out of Jena into the American zone, resettling them in the small town of Oberkochen. Rather than trying to extract or copy Zeiss's optical know-how, the US moved the specific people who possessed it.

Evacuated the specific engineers who carried Zeiss's tacit lens-making skill, since blueprints and patents cannot capture the judgment that makes them work.

Tacit knowledge lives in people, not files, so moving people transfers capability intact.

Blueprints lack the judgment calls needed to reproduce precision, so documents alone fail.

Relocating experts allowed immediate restart of operations, unlike rebuilding from patents.

Leaving experts behind would have handed the Soviets the means to replicate Zeiss's edge.

When a rival gains control of your facility, move the people who hold tacit knowledge, not just documents.

Oberkochen restarted within months and led Western optics; Soviet-run Jena stayed cut off from Western markets for 45 years. The split produced two rival companies bearing the same name and lineage until German reunification in 1990, when Zeiss Oberkochen absorbed Jena's operations — the West German descendant taking over the East German original it had once been evacuated from.