According to Photo rumors, Sigma is working on making their USB Dock compatible with their old lenses with a new firmware update. No sure yet this come to all Sigma lenses or just some of old lenses.
Sigma USB Dock allows you to connect your Sigma Global Vision lenses to your computer in order to update firmware and adjust focus setting parameters using the Sigma Optimization Pro software. Currently only compatible with the Sigma Art, Contemporary, and Sports line lenses.
You can buy Sigma USB Dock for $59.00 from Amazon.com, B&H Photo Video, Adorama.com.
via: PhotoRumors