I noticed that one of the cases today was listed as a precedential ruling...case 17-2149. This particular case was argued on 2018-06-05. I'm assuming that this case took a while due to the large number of patent infringements.

On the other hand, Case 18-2356 was ruled precedential yesterday and it was argued on 2019-08-05. This one only took about two months to decide.

Thanks for posting, Weave!