Further details about the lens gotten from Sony Alpha Rumors seem to point towards that fact that the lens would be shorter and lighter than the Sony’s 100-400mm f/4.5-5.6 G Master lens, will feature a linear focusing motor, and it will cost “around $1,000” which is over 50% lesser than what the Sony counterpart cost ($2,500).
There’s no official word yet from Sigma but based on Nokishita past record, it won’t be long now before the official announcement debuts. Sigma already has a 100-400mm DG Lens for DSLR Cameras