I suppose it depends on the system? I have updated Sigma, TAMRON, and XiaoYi lenses on my Panasonic and Olympus MFT bodies, as well as Panasonic and Olympus with each other: https://support.jp.omsystem.com/en/support/imsg/digicamera/d... (Sadly not an exhaustive list. I have firmware for several more lenses stashed away in my archive, but the upgrade mechanism is the same.)