diff --git a/artifacts/stablecoin-idl.json b/artifacts/stablecoin-idl.json
index b2e88be..0ed6315 100644
--- a/artifacts/stablecoin-idl.json
+++ b/artifacts/stablecoin-idl.json
@@ -125,7 +125,7 @@
         {
           "name": "stablecoin_definition",
           "writable": false,
-          "signer": false,
+          "signer": true,
           "init": false
         },
         {
diff --git a/programs/integration_tests/tests/stablecoin.rs b/programs/integration_tests/tests/stablecoin.rs
index af61a8e..309fdd7 100644
--- a/programs/integration_tests/tests/stablecoin.rs
+++ b/programs/integration_tests/tests/stablecoin.rs
@@ -27,6 +27,10 @@ impl Keys {
     fn user_stablecoin_holding() -> PrivateKey {
         PrivateKey::try_new([43; 32]).expect("valid private key")
     }
+
+    fn stablecoin_definition() -> PrivateKey {
+        PrivateKey::try_new([44; 32]).expect("valid private key")
+    }
 }
 
 impl Ids {
@@ -51,7 +55,9 @@ impl Ids {
     }
 
     fn stablecoin_definition() -> AccountId {
-        AccountId::new([6; 32])
+        AccountId::from(&PublicKey::new_from_private_key(
+            &Keys::stablecoin_definition(),
+        ))
     }
 
     fn price_feed() -> AccountId {
@@ -486,11 +492,12 @@ fn stablecoin_redemption_controller_initializes_and_updates_from_price_feed() {
             Ids::stablecoin_definition(),
             Ids::price_feed(),
         ],
-        vec![],
+        vec![current_nonce(&state, Ids::stablecoin_definition())],
         initialize,
     )
     .unwrap();
-    let witness_set = public_transaction::WitnessSet::for_message(&message, &[]);
+    let witness_set =
+        public_transaction::WitnessSet::for_message(&message, &[&Keys::stablecoin_definition()]);
     let tx = PublicTransaction::new(message, witness_set);
     state
         .transition_from_public_transaction(&tx, 0, current_timestamp)
diff --git a/programs/stablecoin/core/src/lib.rs b/programs/stablecoin/core/src/lib.rs
index cac1a62..336ceb9 100644
--- a/programs/stablecoin/core/src/lib.rs
+++ b/programs/stablecoin/core/src/lib.rs
@@ -91,7 +91,7 @@ pub enum Instruction {
     /// Required accounts (3):
     /// - Redemption controller account (uninitialized, address must match
     ///   `compute_redemption_controller_pda(self_program_id, stablecoin_definition, price_feed)`)
-    /// - Stablecoin token definition account (initialized fungible token)
+    /// - Stablecoin token definition account (authorized initialized fungible token)
     /// - Oracle price feed account (initialized; must decode as the configured
     ///   stablecoin/collateral market price)
     ///
diff --git a/programs/stablecoin/methods/guest/src/bin/stablecoin.rs b/programs/stablecoin/methods/guest/src/bin/stablecoin.rs
index d651540..9e25c68 100644
--- a/programs/stablecoin/methods/guest/src/bin/stablecoin.rs
+++ b/programs/stablecoin/methods/guest/src/bin/stablecoin.rs
@@ -130,6 +130,7 @@ mod stablecoin {
         ctx: ProgramContext,
         #[account(init)]
         controller: AccountWithMetadata,
+        #[account(signer)]
         stablecoin_definition: AccountWithMetadata,
         price_feed: AccountWithMetadata,
         collateral_definition_id: AccountId,
diff --git a/programs/stablecoin/src/redemption_controller.rs b/programs/stablecoin/src/redemption_controller.rs
index a42081e..29c8976 100644
--- a/programs/stablecoin/src/redemption_controller.rs
+++ b/programs/stablecoin/src/redemption_controller.rs
@@ -16,6 +16,7 @@ const CONTROLLER_GAIN_SCALE_I128: i128 = {
 /// Initialize the redemption-rate feedback controller for one stablecoin/feed pair.
 ///
 /// # Panics
+/// - `stablecoin_definition` is not authorized.
 /// - `controller` is already initialized.
 /// - `controller.account_id` does not match the stablecoin/feed PDA.
 /// - `stablecoin_definition` is uninitialized or not a fungible token definition.
@@ -39,6 +40,10 @@ pub fn initialize_redemption_controller(
     max_price_feed_age: u64,
     current_timestamp: u64,
 ) -> Vec<AccountPostState> {
+    assert!(
+        stablecoin_definition.is_authorized,
+        "Stablecoin definition authorization is missing"
+    );
     assert_eq!(
         controller.account,
         Account::default(),
@@ -380,7 +385,7 @@ mod tests {
                 }),
                 nonce: Nonce(0),
             },
-            is_authorized: false,
+            is_authorized: true,
             account_id: stablecoin_definition_id(),
         }
     }
@@ -489,6 +494,28 @@ mod tests {
         assert_eq!(controller.last_update_timestamp, 100);
     }
 
+    #[test]
+    #[should_panic(expected = "Stablecoin definition authorization is missing")]
+    fn initialize_redemption_controller_requires_stablecoin_definition_authorization() {
+        let mut stablecoin_definition = stablecoin_definition_account();
+        stablecoin_definition.is_authorized = false;
+
+        initialize_redemption_controller(
+            uninit_controller_account(),
+            stablecoin_definition,
+            price_feed_account(1_000, 100),
+            STABLECOIN_PROGRAM_ID,
+            collateral_definition_id(),
+            1_000,
+            CONTROLLER_GAIN_SCALE,
+            0,
+            1_000,
+            500,
+            10,
+            100,
+        );
+    }
+
     #[test]
     fn update_redemption_controller_uses_live_price_feed() {
         let post_states = update_redemption_controller(