Is this in or out? And if I missed the mando or went OB, where do I play from?

Out-of-bounds: when a disc is actually OB

A disc is OB only if it is clearly and completely surrounded by the out-of-bounds area (806.02). The painted or marked OB line itself is out-of-bounds. If any part of the disc is still over in-bounds ground, the disc is in-bounds — even if the rest of it is on the line. See our half-in, half-out diagram for the line call.

You do not have to find the disc to rule it OB. If the group agrees there is compelling evidence that it came to rest out-of-bounds, you play it as OB even if it is never found.

The OB penalty and where you play from

Going OB costs one penalty throw. Then you choose your next lie: the previous lie, or a spot up to one metre from where the disc was last in-bounds, perpendicular to the OB line. From that one-metre spot you may also walk farther back on the line of play at no extra cost. No supporting point may be in the OB area when you throw.

Drop zones are only an option when the tournament director has designated one for that hole. Check the caddie book or player meeting notes before assuming one exists.

Mandatories: what counts as a miss

A mandatory (“mando”) defines a restricted plane you may not pass on the wrong side. If any part of the disc clearly enters the restricted plane, you missed the mando (804.01). That is one penalty throw, and your next lie is the mando drop zone, or the previous lie if the TD did not set one.

One trap: you cannot throw a provisional just because you think you might have missed the mando. 809.02.D rules that out. Walk up, let the group decide, then play. For the full provisional rules, see lost discs and provisionals.