diff --git a/project_registry/src/lib.rs b/project_registry/src/lib.rs
index 12905686..9035b19b 100644
--- a/project_registry/src/lib.rs
+++ b/project_registry/src/lib.rs
@@ -761,6 +761,10 @@ impl ProjectRegistry {
         if project.maturity_date > 0 && env.ledger().timestamp() < project.maturity_date {
             panic_with_error!(&env, RegistryError::ProjectNotMature);
         }
+        // Open-ended projects (maturity_date == 0) must be archived before collateral release.
+        if project.maturity_date == 0 && project.status != types::ProjectStatus::Archived {
+            panic_with_error!(&env, RegistryError::ProjectNotArchived);
+        }
 
         let key = DataKey::Collateral(project_id, token.clone());
         let balance: i128 = env.storage().persistent().get(&key).unwrap_or(0);