Rules Analysis
World Flying Disc Federation 2017 Rules of Ultimate
13. Turnovers
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13.5.

Any offensive player may take possession of the disc after a turnover, except:

If, in attempting to intercept a pass, a defender from Team A loses control of the disc due to ground contact, or accidentally drops the disc, then the catch is deemed to have not occurred and any player on Team A may take possession of the disc.

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1
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after an “interception” turnover, in which case the player who made the interception must maintain possession; and

2
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after an offensive receiving foul, in which case the fouled player must take possession.