Lemma 69.13.1. Let $S$ be a scheme. Let $X$ be a Noetherian algebraic space over $S$. Let $\mathcal{F}$ be a coherent $\mathcal{O}_ X$-module. The ascending chain condition holds for quasi-coherent submodules of $\mathcal{F}$. In other words, given any sequence
of quasi-coherent submodules, then $\mathcal{F}_ n = \mathcal{F}_{n + 1} = \ldots $ for some $n \geq 0$.
Proof. Choose an affine scheme $U$ and a surjective étale morphism $U \to X$ (see Properties of Spaces, Lemma 66.6.3). Then $U$ is a Noetherian scheme (by Morphisms of Spaces, Lemma 67.23.5). If $\mathcal{F}_ n|_ U = \mathcal{F}_{n + 1}|_ U = \ldots $ then $\mathcal{F}_ n = \mathcal{F}_{n + 1} = \ldots $. Hence the result follows from the case of schemes, see Cohomology of Schemes, Lemma 30.10.1. $\square$
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