From Sigma:
Thank you for purchasing and using our products.
We would like to announce the update in the lens firmware of the 150-600mm F5-6.3 DG OS HSM | Sports Nikon on the SIGMA Optimization Pro, the dedicated software for the SIGMA USB DOCK.
The latest firmware update improves focusing performance when Continuous servo (AF-C) is in use.
For those customers who own the following products, please update the firmware of the lens via the SIGMA Optimization Pro.
Applicable products:
Firmware version 1.02:
The Sigm USB Dock and Sigma Optimization Pro Software are required to perform the firmware update.
B&H carries the Sigma 150-600mm f/5-6.3 DG OS HSM Sports Lens.