Save $50 on the Sigma f/1.4 MFT prime lenses

Sigma US launched $50 rebates on the three MFT lenses:
16mm f/1.4 at Amazon, FocusCamera, BHphoto,and Adorama.
30mm f/1.4 at Amazon, FocusCamera, BHphoto, and Adorama,
56mm f/1.4 at Amazon, FocusCamera, BHphoto, and  Adorama.