diff --git a/x/auth/tx/builder.go b/x/auth/tx/builder.go
index 7cf3596f342b..d64c927e6524 100644
--- a/x/auth/tx/builder.go
+++ b/x/auth/tx/builder.go
@@ -287,11 +287,17 @@ func (w *wrapper) SetSignatures(signatures ...signing.SignatureV2) error {
 	rawSigs := make([][]byte, n)
 
 	for i, sig := range signatures {
-		var modeInfo *tx.ModeInfo
+		var (
+			modeInfo *tx.ModeInfo
+			any      *codectypes.Any
+			err      error
+		)
 		modeInfo, rawSigs[i] = SignatureDataToModeInfoAndSig(sig.Data)
-		any, err := codectypes.NewAnyWithValue(sig.PubKey)
-		if err != nil {
-			return err
+		if sig.PubKey != nil {
+			any, err = codectypes.NewAnyWithValue(sig.PubKey)
+			if err != nil {
+				return err
+			}
 		}
 		signerInfos[i] = &tx.SignerInfo{
 			PublicKey: any,
diff --git a/x/auth/tx/builder_test.go b/x/auth/tx/builder_test.go
index f7122dd39218..b4c1556e5c3d 100644
--- a/x/auth/tx/builder_test.go
+++ b/x/auth/tx/builder_test.go
@@ -123,6 +123,20 @@ func TestTxBuilder(t *testing.T) {
 	})
 }
 
+func TestSetSignaturesNoPublicKey(t *testing.T) {
+	_, pubkey, _ := testdata.KeyTestPubAddr()
+	txBuilder := newBuilder(nil)
+	sig2 := signing.SignatureV2{
+		Data: &signing.SingleSignatureData{
+			SignMode:  signing.SignMode_SIGN_MODE_DIRECT,
+			Signature: legacy.Cdc.MustMarshal(pubkey),
+		},
+		Sequence: 1,
+	}
+	err := txBuilder.SetSignatures(sig2)
+	require.NoError(t, err)
+}
+
 func TestBuilderValidateBasic(t *testing.T) {
 	// keys and addresses
 	_, pubKey1, addr1 := testdata.KeyTestPubAddr()