The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has evaluated thiodiethylene bis[3‐(3,5‐di‐tert‐butyl‐4‐hydroxyphenyl)propionate] [41484‐35‐9] to derive a maximum concentration at the workplace (MAK value), considering all toxicological endpoints. Available publications and unpublished study reports are described in detail. Critical effects are hepatic hypertrophy and increased liver weight in male rats in a subchronic feeding study with a NOAEL (no observed adverse effect level) of 12.5 mg/kg body weight and day. As there is no irritating potential, the oral study can be used to derive a MAK value of 2 mg/m3 for the inhalable fraction. As the critical effect is systemic, Peak Limitation Category II is assigned. The default excursion factor of 2 is set as no half‐life in blood is known. Classification in Pregnancy Risk Group D is indicated because developmental toxicity studies are lacking. Thiodiethylene bis[3‐(3,5‐di‐tert‐butyl‐4‐hydroxyphenyl)propionate] is not genotoxic. Carcinogenicity studies are not available. The substance is not a contact sensitizer in humans and guinea pigs. Skin contact is not expected to contribute significantly to systemic toxicity.