: Recommended using rounded rectangles instead of standard rectangles or oblong shapes to improve solder paste release and consistency. Contour Courtyards
7351C draft was worked on for 3 years and eventually discarded because Dieter Bergman the architect passed away PCB Libraries Do We Have a New Release of IPC-7351C? - PCB Libraries ipc-7351c pdf
Footprints naming convention: IPC-7351 vs. Expert - PCB Libraries : Recommended using rounded rectangles instead of standard
version, with the intended "C" updates largely absorbed into the newer IPC-7352 Guideline Overview of IPC-7351C ipc-7351c pdf