Lemma 29.41.2. Let $f : X \to S$ be a morphism of schemes. The following are equivalent:

1. The morphism $f$ is universally closed.

2. There exists an open covering $S = \bigcup V_ j$ such that $f^{-1}(V_ j) \to V_ j$ is universally closed for all indices $j$.

Proof. This is clear from the definition. $\square$

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