From the rules page on A/E:
...
# Faction owned capital ships that are in hyperspace are considered territory for the faction that owns them.
# Arrest is not possible aboard all other ships during hyperspace travel.
# Ships, vehicles and other entities that are docked aboard a faction owned capital ship or station is considered the territory of the faction.
Im not sure why hyperspace is listed in item 1, 2 makes it seem that ship class is immaterial and any ship in hyper effects arrest. 3 is really what Im curious about.
If Im on a faction owned Capital ship entering into enemy territory is that capital ship consider sovereign ground like a mobile faction controlled land mass?
Umm, the '..all other...' part of #2 is referring to #1 - ie you can arrest on a capital no matter what, but freighters and fighters cannot be arrested on in hyper.
And yes capital ships are considered the factions territory for purposes of A/E, so if you are in an enemy space, they cannot arrest you on your capital so long as they don't meet any of the requisites for being able to arrest.
Seems like you could merge 1 and 2 to make more sense.
Faction owned capital ships that are in hyperspace are considered territory for the faction that owns them. Arrest is not possible aboard (any) other ships during hyperspace travel.
ASims do not have the ability (so far as I can tell) to directly edit the rules pages (bar the Guide, I think, which will be removed at some point anyway).