Pickup
Picks up other Pokémon's used and Flung held items. May also pick up an item after battle.
Full effect
At the end of each turn, if another Pokémon consumed or Flung a held item that turn, this Pokémon picks up the item if it is not already holding one. After each battle, this Pokémon has a 10% chance of picking up an item if it is not already holding one. The Air Balloon and Eject Button cannot be picked up. The items that may be found vary by game, and, since Pokémon Emerald, by the Pokémon's level. This ability is checked after the battle ends, at which point any temporary ability changes have worn off.
In game description
The Pokémon may pick up an item another Pokémon used during a battle. It may pick up items outside of battle, too.
Pokemon with Pickup
Meowth
#0190
Aipom
#0216
Teddiursa
#0231
Phanpy
#0263
Zigzagoon
#0264
Linoone
#0417
Pachirisu
#0424
Ambipom
#0446
Munchlax
#0506
Lillipup
#0659
Bunnelby
#0660
Diggersby
#0702
Dedenne
#0710
Pumpkaboo Average
#0711
Gourgeist Average
#0731
Pikipek
hidden
#0732
Trumbeak
hidden
#0924
Tandemaus
#0971
Greavard
Using Pickup in Cobblemon
Abilities are passive and always active, so Pickup costs you nothing to run. If it is marked hidden on a species above, expect it to be harder to obtain: servers differ in whether hidden abilities come from breeding, an Ability Patch, or events.
See the Pokedex for which abilities each species can have, and IVs, EVs and breeding for how to actually pass one down.