Possess

Possess is the term used to describe who has a card at a given time. It is similar to the term Control, but it also applies to locations other than the field, such as the hand or Deck.

This term was first introduced in Abyss Rising, specifically for use with the Madolche archtype. It is a part of the Problem-Solving Card Text and clarifies that possession of a card includes having a card in your hand or Deck, or attempting to Summon that monster.