[mmiles8]

Somebody once told me that you have to do more than 50% of the damage your pet has dealt in order to get full exp from the mob.

This is because that's how it was in classic, and up until POP.

Q: How do pets affect the experience earned, both while soloing and while in a group?
A: When soloing if the pet does over 50% damage it takes 50% of the experience. When grouped pets take a flat 1% of the experience.

Q: Does the type of pet determine how much experience is taken in a kill?
A: The type of pet chosen has no direct influence on how much experienced is derived from each kill. However, different pets have different damage outputs, and mobs such as water or air pets can do large damage quickly, easily doing over 50% of the overall damage which does reduce the experience obtained from killing the mob.

It was not changed until June 5, 2002.

JUNE 5, 2002

Pets take 75% of the experience from a creature if no player does damage to that creature.
Pets take ZERO experience from a creature unless no player does damage to that creature.
The exception to the above rule is Dire Charmed pets, which will take a share of the experience scaled by the amount of damage they do. In most situations (with an active party, for example) the Dire Charmed pet will not take experience. Like all pets, they will take 75% of the experience if no PC does damage to the target. As long as a player does damage to a creature, a Dire Charmed pet will never take more experience than it used to.