diff --git a/ndn-cpp/security/identity/identity-storage.hpp b/ndn-cpp/security/identity/identity-storage.hpp
index 8b06e2a..52ec3b4 100644
--- a/ndn-cpp/security/identity/identity-storage.hpp
+++ b/ndn-cpp/security/identity/identity-storage.hpp
@@ -127,7 +127,7 @@
    * @param allowAny If false, only a valid certificate will be returned, otherwise validity is disregarded.
    * @return The requested certificate.
    */
-  virtual ptr_lib::shared_ptr<Data> 
+  virtual ptr_lib::shared_ptr<Certificate> 
   getCertificate(const Name &certificateName, bool allowAny = false) = 0;