Sigma filed a patent (2013-3324) in Japan for a 25mm f/1.4 lens for Micro Four Thirds cameras. Sigma currently has a 19mm f/2.8 and 30mm f/2.8 lenses for MFT. Both models are currently on sale at 50% off (two lenses for the price of one).
Panasonic also recently filed a patent for a new 25mm f/1.4 Summilux lens to replace their current Panasonic Leica DG Summilux 25mm f/1.4 ASPH model. The design of the patented lenses is very similar:
