Lemma 93.6.1. The functor

$p : \textit{FÉt} \longrightarrow (\mathit{Sch}/S)_{fppf}$

defines a stack in groupoids over $(\mathit{Sch}/S)_{fppf}$.

Proof. Fppf descent for finite étale morphisms follows from Descent, Lemmas 35.34.1, 35.20.23, and 35.20.29. Details omitted. $\square$

Comment #6272 by Owen on

'stack in groupoids' -> this is not true since the fiber categories are not groupoids.

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