Here are a few pictures I found in the photo galleries:
Please don't take offence if it's you or your picture.
The first two, OK, they're waves but the SUPer has caught them well before a shortboard could ever catch them. What if the guy on the shoulder paddled back the other way and went to catch the wave where it actually becomes a wave? Would he be dropping in? What if one of the three guys sitting paddled across a few metres and went to take that wave as a left? Would they be snaking or would the SUP be dropping in?
The third one, the guys are riding a swell before it's even a wave. What should the surfers on the inside do? Are they allowed to paddle for the wave and call the ski and SUPer off? Because it's not even a wave yet, and it looks like a righthander. Or should it belong to the people riding the swell?
The fourth one, it's also not a wave but the SUPer's "riding" it. The guy on the shortboard's given it up, but IMHO he's got right of way. I.e. if there were two guys on shortboards paddling and one was paddling ridiculously way out of position before it broke and claimed it you'd just ignore him and call him off. But that's a bit hard to do to a SUP, because they can ride swell before it becomes a wave and because they're already standing, so they're always "riding" the wave before anyone else as soon as they catch the swell/wave's momentum.
I'm curious to hear what you guys think? I'll post my (obviously biased) ideas later.