diff --git a/runtime/src/system_program.rs b/runtime/src/system_program.rs
index 8702c5c01d..9049e999a3 100644
--- a/runtime/src/system_program.rs
+++ b/runtime/src/system_program.rs
@@ -85,7 +85,7 @@ pub fn entrypoint(
         // All system instructions require that accounts_keys[0] be a signer
         if keyed_accounts[FROM_ACCOUNT_INDEX].signer_key().is_none() {
             info!("account[from] is unsigned");
-            Err(ProgramError::InvalidArgument)?;
+            Err(ProgramError::MissingRequiredSignature)?;
         }
 
         match instruction {
@@ -96,7 +96,7 @@ pub fn entrypoint(
             } => create_system_account(keyed_accounts, lamports, space, &program_id),
             SystemInstruction::Assign { program_id } => {
                 if !system_program::check_id(&keyed_accounts[FROM_ACCOUNT_INDEX].account.owner) {
-                    Err(ProgramError::AssignOfUnownedAccount)?;
+                    Err(ProgramError::IncorrectProgramId)?;
                 }
                 assign_account_to_program(keyed_accounts, &program_id)
             }
@@ -245,7 +245,7 @@ mod tests {
         };
         let data = serialize(&instruction).unwrap();
         let result = entrypoint(&system_program::id(), &mut keyed_accounts, &data, 0);
-        assert_eq!(result, Err(ProgramError::AssignOfUnownedAccount));
+        assert_eq!(result, Err(ProgramError::IncorrectProgramId));
         assert_eq!(from_account.owner, new_program_owner);
     }
 
diff --git a/runtime/tests/system.rs b/runtime/tests/system.rs
index 0a3febc7dd..72b45e81a2 100644
--- a/runtime/tests/system.rs
+++ b/runtime/tests/system.rs
@@ -49,7 +49,7 @@ fn test_system_unsigned_transaction() {
         system_bank.bank.process_transaction(&tx),
         Err(BankError::InstructionError(
             0,
-            InstructionError::ProgramError(ProgramError::InvalidArgument)
+            InstructionError::ProgramError(ProgramError::MissingRequiredSignature)
         ))
     );
     assert_eq!(system_bank.bank.get_balance(&from_keypair.pubkey()), 50);
diff --git a/sdk/src/native_program.rs b/sdk/src/native_program.rs
index cdbd96f93a..d1eaed03bb 100644
--- a/sdk/src/native_program.rs
+++ b/sdk/src/native_program.rs
@@ -17,8 +17,11 @@ pub enum ProgramError {
     /// An account's userdata was too small
     UserdataTooSmall,
 
-    /// SystemInstruction::Assign was attempted on an account unowned by the system program
-    AssignOfUnownedAccount,
+    /// The account did not have the expected program id
+    IncorrectProgramId,
+
+    /// A signature was required but not found
+    MissingRequiredSignature,
 
     /// CustomError allows on-chain programs to implement program-specific error types and see
     /// them returned by the Solana runtime. A CustomError may be any type that is serialized