At Photokina 2016 Focus Numerique had an interview with the President of Sigma, Mr. Kazuto Yamaki and Mr. Yamaki stated that Sigma will make FE lenses for Sony full frame E-mount mirrorless cameras in the near future:
The future of FE mount is beaming. So yes we will come out of FE mount objectives in the future.
Sigma recently announced 8 High Speed Cinema Lenses, including 3 zoom lenses and 5 prime lenses. But the upcoming Sigma FE lenses mean the general photography lenses. So, what do you expect from Sigma?
Stay tuned for more info.
Read more: Sigma Rumors