diff --git a/cartographer_ros_msgs/msg/SubmapEntry.msg b/cartographer_ros_msgs/msg/SubmapEntry.msg
index 605de24..6cbd4ea 100644
--- a/cartographer_ros_msgs/msg/SubmapEntry.msg
+++ b/cartographer_ros_msgs/msg/SubmapEntry.msg
@@ -12,5 +12,5 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-uint32 submap_version
+int32 submap_version
 geometry_msgs/Pose pose