diff --git a/AUTHORS b/AUTHORS
index b1e4ddf9..eb3534a6 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -8,3 +8,4 @@
 
 Google Inc.
 Opera Software ASA
+Vewd Software AS
diff --git a/snapshot/x86/cpuid_reader.h b/snapshot/x86/cpuid_reader.h
index 0fd02cfd..b6782afb 100644
--- a/snapshot/x86/cpuid_reader.h
+++ b/snapshot/x86/cpuid_reader.h
@@ -12,6 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+#ifndef CRASHPAD_SNAPSHOT_X86_CPUID_READER_H_
+#define CRASHPAD_SNAPSHOT_X86_CPUID_READER_H_
+
 #include <stdint.h>
 
 #include <string>
@@ -61,3 +64,5 @@ class CpuidReader {
 
 }  // namespace internal
 }  // namespace crashpad
+
+#endif  // CRASHPAD_SNAPSHOT_X86_CPUID_READER_H_
diff --git a/util/win/nt_internals.h b/util/win/nt_internals.h
index a2a88b77..dad04056 100644
--- a/util/win/nt_internals.h
+++ b/util/win/nt_internals.h
@@ -12,6 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+#ifndef CRASHPAD_UTIL_WIN_NT_INTERNALS_H_
+#define CRASHPAD_UTIL_WIN_NT_INTERNALS_H_
+
 #include <windows.h>
 #include <winternl.h>
 
@@ -92,3 +95,5 @@ void RtlGetUnloadEventTraceEx(ULONG** element_size,
                               void** event_trace);
 
 }  // namespace crashpad
+
+#endif  // CRASHPAD_UTIL_WIN_NT_INTERNALS_H_