diff --git a/unit/test-gatt.c b/unit/test-gatt.c
index 6a5e5a4..0d58dc1 100644
--- a/unit/test-gatt.c
+++ b/unit/test-gatt.c
@@ -820,6 +820,14 @@ static const struct test_step test_write_5 = {
 	.length = 0x03
 };
 
+static const struct test_step test_write_6 = {
+	.handle = 0x0007,
+	.func = test_write,
+	.expected_att_ecode = 0x0c,
+	.value = write_data_1,
+	.length = 0x03
+};
+
 static void att_write_cb(struct gatt_db_attribute *att, int err,
 								void *user_data)
 {
@@ -2937,5 +2945,11 @@ int main(int argc, char *argv[])
 			raw_pdu(0x12, 0x07, 0x00, 0x01, 0x02, 0x03),
 			raw_pdu(0x01, 0x12, 0x07, 0x00, 0x05));
 
+	define_test_client("/TP/GAW/CL/BI-06-C", test_client, service_db_1,
+			&test_write_6,
+			SERVICE_DATA_1_PDUS,
+			raw_pdu(0x12, 0x07, 0x00, 0x01, 0x02, 0x03),
+			raw_pdu(0x01, 0x12, 0x07, 0x00, 0x0c));
+
 	return tester_run();
 }