Sorry if i wasnt clear, but what i mean with "based on" in this case is just the content sharing, not that it is build directly further on from MHP3rd. It is just a matter of how one define "based on". One can say that it is based on MH3, but also include stuff from MH3rd, that is fine too But it doesnt matter that much though i think because all Monster Hunter games share the same gameplay mechanics, and MHP3rd and TriG are both portable games which are reasons that makes the games very popular.Having some MHP3 monsters doesn't mean "it's also based on MHP3". They're two different games. MH3G is based on MH3. It has monsters from other entries as well, but it's not based on them.
I was just wondering about the relationship between MHP3rd and TriG because i had seen people referring to TriG as being the 3rd release of the game. From what i gathered of the previous replies in this thread, seeing that TriG is not a brand new game, i understand that it has stuff (or being based on) from MH3 and MHP3rd, and then some new stuff is added as well. So TriG has stuff from the most popular MH game in it as well. That was the thing i was wondering about =)
EDIT: I added some text.