Sigma patented the design for the 20mm f/1.4 MFT lens, 35mm f/1.4 MFT lens and a new 40mm f/1.4 MFT lens. The very interesting part is that the optical design of the 20mm lens corresponds to the OM Digital 20mm lens. So it sounds likely that Sigma is still designing lenses for the MFT system that they license to others.