The new Sigma 14-24mm f/2.8 Art full frame DSLR lens will be officially released on March 9th, 2018 according to Nokishita. The price in Japan is rumored to be ￥164,700 or around $1,500 (US pricing not yet available, check this page for updates). For comparison, the Nikkor 14-24mm f/2.8G ED lens is currently priced at $1,896.95.
Additional information on the new Sigma 14-24mm f/2.8 len can be found here:
Sigma officially announces their new 14-24mm f/2.8 Art full frame DSLR lens
