Fouls (3.C): It is the responsibility of all players to avoid contact in every way possible.
Avoid contact in every way reasonably possible, while still playing ultimate. Some contact is inevitable, but players have an affirmative obligation to make reasonable efforts to avoid contact.
Some fouls carry some extra provisions, as listed below.
Strip: If a foul causes a player to lose possession of the disc, it is a strip. A strip is a subset of fouls and is treated the same way.
Initiating contact with a disc in a player's possession is a foul. Sustained contact with, and control of, a non-spinning disc is required to establish possession (3.J). A player may not call a strip if they had only momentary contact with or lacked control of the disc prior to an opponent contacting the disc.