The verbatim Shopify answer on Catalog opt-out
No. Shopify states it verbatim on the Catalog help page: 'you can't opt out of Shopify Catalog itself.'1 What merchants can do is block individual AI channels from accessing products through two controls: 'Shopify Catalog access' and 'Direct checkout' settings. Inclusion in the underlying Catalog is automatic; per-channel surfacing is opt-in/opt-out per channel.
What you CAN block
Per-channel access and per-channel checkout behavior, both controlled from the Agentic Storefronts admin at admin.shopify.com/agentic.3 A merchant can turn off Catalog access for ChatGPT while leaving it on for Perplexity, or vice versa. Or leave discovery on everywhere and disable in-chat direct checkout on specific channels so the buyer always finishes on the merchant's storefront.
The two controls
Two settings per channel: Shopify Catalog access and Direct checkout. Catalog access on/off determines whether the channel can recommend the products at all. Direct checkout on/off determines whether the buyer can complete checkout inside the AI conversation or has to come back to the merchant's storefront. Catalog access off implies no surfacing; Direct checkout off implies recommendations stay on but conversion routes to the storefront.
Per-channel decision checklist
Five questions to ask per channel before toggling. Most stores want all channels on for discovery. Direct checkout is the more interesting decision — disabling it on a channel costs in-chat conversion but preserves storefront upsell, post-purchase flows, and exact attribution.