Who were the only German businessmen to be executed in 1946 for their roles in the Holocaust?

Bruno Tesch and Karl Weinbacher were executed for a critical support role in the Holocust: they were principles of the chemical manufacturer Testa, which sold Zyklon-B to the Reich for use in the gas chambers. Hydrogen cyanide had been employed as a legitimate pesticide and de-lousing agent for many years before World War II. Because of its danger, the odorless deadly gas was sold spiced with an odorant to alert humans accidentally exposed to it.

Tesch and Weinbacher had their necks stretched because they were shown to have knowingly sold this product sans odor, reflecting Testa's complicity in its intended use upon humans. (A third Testa employee was acquitted, having inadequate knowledge of the firm's operations.)