Out with the old and in with the new. Now that Canon has updated their 400mm and 600mm lenses into the III series, B&H has discounted the previous long-time kings of sporting events and wildlife portraiture.
The Canon EF 400mm f/2.8L IS III USM and EF 600mm f/4L IS III USM, costing $11,999 and $12,999 respectively, began shipping to customers in December 2018. While the 600mm III seems to still be catching up to demand, I've seen the 400mm III has been readily in stock, and this must mean that it's time to start phasing out the previous generation.
Taking a $2,000 price cut, you can now pick up one of these brand new previous-generation Canon EF 400mm f/2.8L IS II USM lenses for $7,999 and the EF 600mm f/4L IS II USM for $9,499. Both of these lenses were first introduced in 2011 and each saw a great reduction in weight compared to their first generation models, with the 600mm also gaining a full meter of better close focusing performance. They've been beloved workhorses and just because there is something newer out there, doesn't mean these stop being phenomenal. If you have the coin, the temptation just got a little harder to fight.