diff --git a/service/native/libs/libclat/clatutils.cpp b/service/native/libs/libclat/clatutils.cpp
index 64e5b91..c6a9781 100644
--- a/service/native/libs/libclat/clatutils.cpp
+++ b/service/native/libs/libclat/clatutils.cpp
@@ -29,9 +29,6 @@
 #include "checksum.h"
 }
 
-// Sync from system/netd/include/netid_client.h.
-#define MARK_UNSET 0u
-
 namespace android {
 namespace net {
 namespace clat {
@@ -128,7 +125,7 @@
 
     // Socket's mark affects routing decisions (network selection)
     // An fwmark is necessary for clat to bypass the VPN during initialization.
-    if ((mark != MARK_UNSET) && setsockopt(s, SOL_SOCKET, SO_MARK, &mark, sizeof(mark))) {
+    if (setsockopt(s, SOL_SOCKET, SO_MARK, &mark, sizeof(mark))) {
         int ret = errno;
         ALOGE("setsockopt(SOL_SOCKET, SO_MARK) failed: %s", strerror(errno));
         close(s);
@@ -176,7 +173,7 @@
     }
 
     // Socket's mark affects routing decisions (network selection)
-    if ((mark != MARK_UNSET) && setsockopt(s, SOL_SOCKET, SO_MARK, &mark, sizeof(mark))) {
+    if (setsockopt(s, SOL_SOCKET, SO_MARK, &mark, sizeof(mark))) {
         int ret = errno;
         ALOGE("setsockopt(SOL_SOCKET, SO_MARK) failed: %s", strerror(errno));
         close(s);