I couldn't find any legal requirements, but the ESA recommends a reentry withtin 25 years of mission completion to reduce waste in orbit. https://www.esa.int/S

I couldn't find any legal requirements, but the ESA recommends a reentry withtin 25 years of mission completion to reduce waste in orbit. https://www.esa.int/Safety_Security/Space_Debris/Mitigating_space_debris_generation https://www.esa.int/Safety_Security/Space_Debris/Mitigating_...