Is this correct that the lel greater than 30 trainers catch the same Pokemons in the same place?

Someone told me that trainers whose level are less than 30 catches the same Pokemon of random CP in the same place. However the level of great than 30 trainers catch a Pokemon of the same CP value, which means if you are level 30 catching a 100% Pokemon somewhere, the other trainers of level great than 30 will also catch a 100% Pokemon in the same place.
Is this true?