Olympus E-M5 III has a Micro Four Thirds lens mount and currently there are 123 native lenses available for this mount.
The latest released lenses that are compatible with the E-M5 Mark III are the Rokinon 7.5mm f3.5 Fisheye, the Samyang 7.5mm F3.5 Fisheye MFT and the Panasonic 100-400mm F4.0-6.3 II.
E-M5 Mark III also has a sensor based image stabilization system that is up to 6.5-stops effective which means that all of these lenses will be stabilized when used on the E-M5 Mark III.
Since Olympus E-M5 III has a Four Thirds sensor, it has a focal length multiplier of 2x so you have to multiply lenses original focal length with this multiplier to find the Full Frame equivalent focal length of the lens when mounted on E-M5 Mark III.
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Olympus E-M5 III Lenses with Image Stabilization
Olympus E-M5 III Lenses with Weather Sealings