If any Pokemon in the party are holding exp. shares, then the experience is split in half. One half goes to the Pokemon that participated in defeating/catching the opponent, and the other half goes to exp. share holders. For example, if two Pokemon are holding exp. shares and neither of them participated in defeating/catching the opponent, then each of them will get 1/4 of the experience, because (1/2)/2=1/4. If one of them participated in defeating/catching the opponent, and no other team members participated, then the participant will get 1/4 of the experience for holding the exp. share and an additional 1/2 for participating, while the other exp. share holder will get 1/4 of the experience.
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