diff --git a/ai-task.md b/ai-task.md
index 239ce5c..fe0a957 100644
--- a/ai-task.md
+++ b/ai-task.md
@@ -1,6 +1,6 @@
-# Verify a purchase
+# Connect it to a user
 
-Add a fictional store adapter and verification. Persist accepted evidence without granting access. Invalid evidence must be a negative verdict; an upstream outage must be an error. Prove that binding is still unimplemented.
+Add server-only ownership binding, subscription status, and entitlement reads. Verify the same owner can repeat a bind, another owner cannot take it, and verification credentials cannot bind. Show Alice gaining Premium.
 
 Use the existing reviewed prototype where it satisfies the installed contract.
 Run the backend, inspect the result, correct problems, and rerun the affected check.
diff --git a/checkpoint.json b/checkpoint.json
index 5053480..2339583 100644
--- a/checkpoint.json
+++ b/checkpoint.json
@@ -1,8 +1,8 @@
 {
-  "step": 2,
-  "id": "02-verify",
-  "title": "Verify a purchase",
-  "built": "Fixture store adapter + purchase persistence",
-  "result": "Valid evidence is saved. Alice still has no access.",
-  "previous": "01-contract"
+  "step": 3,
+  "id": "03-bind",
+  "title": "Connect it to a user",
+  "built": "Server authorization + atomic binding + entitlement reads",
+  "result": "Alice gets Premium. Another user cannot take the purchase.",
+  "previous": "02-verify"
 }
diff --git a/provider.mjs b/provider.mjs
index 08c4ada..7019c85 100644
--- a/provider.mjs
+++ b/provider.mjs
@@ -97,6 +97,30 @@ export function createProvider(path, now) {
         environment: "local-fixture",
       };
     },
+    bindPurchase(input) {
+      if (input.store !== FIXTURE.store) return { error: "UNSUPPORTED_STORE" };
+      if (typeof input.evidence !== "string")
+        return { error: "INVALID_REQUEST" };
+      return db.transaction(() => {
+        const key = fingerprint(input.evidence);
+        db.query(
+          "UPDATE purchases SET user_id = ? WHERE fingerprint = ? AND user_id IS NULL",
+        ).run(input.userId, key);
+        const row = db
+          .query("SELECT user_id FROM purchases WHERE fingerprint = ?")
+          .get(key);
+        return { bound: row?.user_id === input.userId };
+      })();
+    },
+    entitlements: (input) => entitlements(input.userId),
+    subscriptionStatus(input) {
+      const snapshots = rowsFor(input.userId).map(snapshot);
+      const subscription = snapshots.find((row) => row.active) ?? snapshots[0];
+      return {
+        active: snapshots.some((row) => row.active),
+        ...(subscription ? { subscription } : {}),
+      };
+    },
   };
 
   async function fetch(request) {
diff --git a/scenario.mjs b/scenario.mjs
index 53adc4c..2df52f6 100644
--- a/scenario.mjs
+++ b/scenario.mjs
@@ -12,6 +12,11 @@ export const STAGES = [
     "title": "Verify a purchase",
     "built": "Fixture store adapter + purchase persistence",
     "result": "Valid evidence is saved. Alice still has no access."
+  },
+  {
+    "title": "Connect it to a user",
+    "built": "Server authorization + atomic binding + entitlement reads",
+    "result": "Alice gets Premium. Another user cannot take the purchase."
   }
 ];
 
@@ -74,7 +79,7 @@ export function createScenario(runtime) {
       );
       check(
         "Verification does not grant access",
-        runtime.provider.inspect().access.productIds,
+        (await run("entitlements", { userId: FIXTURE.userId })).body.productIds,
         [],
       );
       check(
@@ -99,6 +104,41 @@ export function createScenario(runtime) {
         ).body.error.code,
         "VERIFICATION_FAILED",
       );
+    } else if (stage === 2) {
+      check(
+        "Verification credentials cannot bind a user",
+        (
+          await run(
+            "bindPurchase",
+            { ...evidence, userId: FIXTURE.userId },
+            "verification",
+          )
+        ).body.error.code,
+        "FORBIDDEN",
+      );
+      check(
+        "The server binds Alice",
+        (await run("bindPurchase", { ...evidence, userId: FIXTURE.userId }))
+          .body.bound,
+        true,
+      );
+      check(
+        "Repeating the same binding succeeds",
+        (await run("bindPurchase", { ...evidence, userId: FIXTURE.userId }))
+          .body.bound,
+        true,
+      );
+      check(
+        "Bob cannot take Alice's purchase",
+        (await run("bindPurchase", { ...evidence, userId: "demo_bob" })).body
+          .bound,
+        false,
+      );
+      check(
+        "Alice can access Premium",
+        (await run("entitlements", { userId: FIXTURE.userId })).body.productIds,
+        [FIXTURE.productId],
+      );
     }
     const entry = {
       step: stage + 1,
diff --git a/verify.mjs b/verify.mjs
index ac257f3..117ecca 100644
--- a/verify.mjs
+++ b/verify.mjs
@@ -13,7 +13,7 @@ export async function verifyLab() {
   try {
     for (const stage of STAGES) await lab.scenario.advance();
     checks.push(...lab.scenario.history.flatMap(entry => entry.checks));
-    const unsupported = "bindPurchase";
+    const unsupported = "eraseUser";
     const response = await requestOperation(lab.runtime.baseUrl, unsupported, {});
     check("An unimplemented operation is explicitly refused", response.body.error.code, "UNSUPPORTED_PROFILE");
     check("Untrusted browser origins are refused", (await fetch(lab.runtime.baseUrl + "/demo/advance", { method: "POST", headers: { origin: "https://untrusted.example" } })).status, 403);