Sigma filed patent P2019-23693A that appears to be for the Olympus M. Zuiko Digital ED 45mm f/1.2 Pro lens - see this comparison:
Lens information from the patent:
- Publication date: February 14, 2019
- Focal length: 44.10 mm
- F number: 1.28
- Angle of view: 27.57
- Image height: 10.82 mm
- Lens length: 101.22 mm
Via Hi-lows-note