B&H has loads of Sigma lenses on sale this week as part of its WPPI promo. I’m not even going to try to summarize all of the deals but there 186 items from Sigma in total. Check them out here at B&H Photo.
And if you don’t want everything from Sigma to show up, you can see only the Sigma Art lenses on sale here.
In order to get the full savings, you have to use the coupon code BHWPPI16 at checkout. Actually, you should probably try that code for any purchases you make at B&H this week to see if your purchase has an additional discount available.