diff --git a/doc/manual/rl-next/multiple-signatures.md b/doc/manual/rl-next/multiple-signatures.md
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@@ -0,0 +1,15 @@
+---
+synopsis: "Multiple signatures support in store urls"
+issues:
+prs: [12976]
+---
+
+Added support for a `secretKeyFiles` URI parameter in Nix store URIs, allowing multiple signing key files to be specified as a comma-separated list.
+This enables signing paths with multiple keys. This helps with [RFC #149](https://github.com/NixOS/rfcs/pull/149) to enable binary cache key rotation in the NixOS infra.
+
+Example usage:
+
+```bash
+nix copy --to "file:///tmp/store?secret-keys=/tmp/key1,/tmp/key2" \
+  "$(nix build --print-out-paths nixpkgs#hello)"
+```