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Corollary 9.2.9.2. Let $\mu $ be an uncountable cardinal and let $\operatorname{\mathcal{D}}$ be the limit of a finite diagram

\[ \mathscr {F}: \operatorname{\mathcal{C}}\rightarrow \operatorname{\mathcal{QC}}_{< \mu } \quad \quad (C \in \operatorname{\mathcal{C}}) \mapsto \mathscr {F}(C) \]

satisfying the following conditions:

$(1)$

For each vertex $C \in \operatorname{\mathcal{C}}$, the $\infty $-category $\mathscr {F}(C)$ admits small filtered colimits.

$(2)$

For each edge $e: C \rightarrow C'$ of $\operatorname{\mathcal{C}}$, the functor $\mathscr {F}(e): \mathscr {F}(C) \rightarrow \mathscr {F}(C')$ is finitary.

Let $D$ be an object of $\operatorname{\mathcal{D}}$. If the image of $D$ in each $\mathscr {F}(C)$ is compact, then $D$ is compact.

Proof. Apply Proposition 9.2.9.1 in the special case where $\kappa = \aleph _0$ and $\lambda = \Omega $ is a fixed strongly inaccessible cardinal. $\square$