So inquisitive mind's need to know.
If you mean, how come the Bosch 3300 no longer works for Honda motorcycles, it's because Bosch changed the shape of the baseplate, so the plate with the drain holes contacts the metal on the engine face, inhibiting a proper seal.
I'm not 100% sure if this is a problem on the Shadows, but it definitely is on the CB1100.
On the CB1100 forum there are several people who experienced leaking from the Bosch filter seal because it couldn't seat all the way down the threads.
As I stated before, I use the Fram PH6017A with the silicone drainback valve on my CB1100. $6.50 each.
The ST6607 seem to work well on my Shadows and they're only $3 each. Lots of Goldwing riders use the ST6607 too. It's a perfectly good filter, and made in the USA too.
If my Honda dealer didn't charge $20 for a Chinese made Honda filter, I would not have bothered looking for alternatives. I suppose I should thank them for showing me the light! 😉🍀