diff --git a/net-libs/ignition-transport/files/protobuf3.patch b/net-libs/ignition-transport/files/protobuf3.patch
new file mode 100644
index 0000000000000..c5cdd32a714b3
--- /dev/null
+++ b/net-libs/ignition-transport/files/protobuf3.patch
@@ -0,0 +1,12 @@
+Index: ignition-transport-1.1.0/include/ignition/transport/RepHandler.hh
+===================================================================
+--- ignition-transport-1.1.0.orig/include/ignition/transport/RepHandler.hh
++++ ignition-transport-1.1.0/include/ignition/transport/RepHandler.hh
+@@ -22,6 +22,7 @@
+ #pragma warning(push, 0)
+ #endif
+ #include <google/protobuf/message.h>
++#include <google/protobuf/stubs/casts.h>
+ #ifdef _MSC_VER
+ #pragma warning(pop)
+ #endif
diff --git a/net-libs/ignition-transport/ignition-transport-1.1.0.ebuild b/net-libs/ignition-transport/ignition-transport-1.1.0.ebuild
index f965d2fac1271..94fde8b25100b 100644
--- a/net-libs/ignition-transport/ignition-transport-1.1.0.ebuild
+++ b/net-libs/ignition-transport/ignition-transport-1.1.0.ebuild
@@ -25,6 +25,7 @@ RDEPEND="${DEPEND}"
 DEPEND="${DEPEND}
 	virtual/pkgconfig"
 CMAKE_BUILD_TYPE=RelWithDebInfo
+PATCHES=( "${FILESDIR}/protobuf3.patch" )
 
 src_configure() {
 	# upstream appends this conditionally...