diff --git a/.changeset/mosaic-floating-ui-external.md b/.changeset/mosaic-floating-ui-external.md
new file mode 100644
index 00000000000..2de34daa1f3
--- /dev/null
+++ b/.changeset/mosaic-floating-ui-external.md
@@ -0,0 +1,5 @@
+---
+'@clerk/mosaic': patch
+---
+
+`@floating-ui/react` is now installed as a dependency of `@clerk/mosaic` instead of being bundled into its output, so apps that already use it can share a single copy.
diff --git a/packages/mosaic/bundlewatch.config.json b/packages/mosaic/bundlewatch.config.json
index 2325ac6ed4a..bf7a2450e74 100644
--- a/packages/mosaic/bundlewatch.config.json
+++ b/packages/mosaic/bundlewatch.config.json
@@ -1,6 +1,6 @@
 {
   "files": [
-    { "path": "./dist/index.js", "maxSize": "110KB" },
+    { "path": "./dist/index.js", "maxSize": "75KB" },
     { "path": "./dist/styles.css", "maxSize": "12KB" }
   ]
 }
diff --git a/packages/mosaic/scripts/check-bundle.mjs b/packages/mosaic/scripts/check-bundle.mjs
index 0ce65fde9f4..b1527050c58 100644
--- a/packages/mosaic/scripts/check-bundle.mjs
+++ b/packages/mosaic/scripts/check-bundle.mjs
@@ -26,6 +26,10 @@ if (!/(?:from|import)\s*['"]@clerk\/shared(?:\/[^'"]*)?['"]/.test(source)) {
   );
 }
 
+if (!/(?:from|import)\s*['"]@floating-ui\/react(?:\/[^'"]*)?['"]/.test(source)) {
+  throw new Error('Published Mosaic JS does not import @floating-ui/react; it should be an external dependency.');
+}
+
 console.log(
-  '✅ Mosaic bundle is client-boundaried, imports @clerk/shared, and is free of UI, Emotion, and StyleX runtime imports',
+  '✅ Mosaic bundle is client-boundaried, imports @clerk/shared and @floating-ui/react, and is free of UI, Emotion, and StyleX runtime imports',
 );
diff --git a/packages/mosaic/tsdown.config.mts b/packages/mosaic/tsdown.config.mts
index 700229ba6a7..8d25f3fd9f1 100644
--- a/packages/mosaic/tsdown.config.mts
+++ b/packages/mosaic/tsdown.config.mts
@@ -16,7 +16,7 @@ export default defineConfig({
   tsconfig: './tsconfig.json',
   deps: {
     neverBundle: ['react', 'react-dom', /^@clerk\/shared(\/.*)?$/],
-    alwaysBundle: [/^@stylexjs\//, /^@floating-ui\//],
+    alwaysBundle: [/^@stylexjs\//],
     onlyBundle: false,
   },
   plugins: [