diff --git a/Control/AthenaIPCTools/src/AthenaSharedMemoryTool.cxx b/Control/AthenaIPCTools/src/AthenaSharedMemoryTool.cxx
index b6cc2cf8c3599e9e981358ef4356792bb19ceaf2..177691167bcac34298dab0e9129342ebaf7bd863 100644
--- a/Control/AthenaIPCTools/src/AthenaSharedMemoryTool.cxx
+++ b/Control/AthenaIPCTools/src/AthenaSharedMemoryTool.cxx
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2021 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2022 CERN for the benefit of the ATLAS collaboration
 */
 
 /* file contains the implementation for the AthenaSharedMemoryTool class.
@@ -17,6 +17,7 @@
 
 const std::size_t maxTokenLength = 512;
 
+namespace {
 struct ShareEventHeader {
    enum ProcessStatus { CLEARED, FILLED, LOCKED, UNLOCKED, PARTIAL, SHARED, UNKNOWN };
    ProcessStatus evtProcessStatus;
@@ -28,6 +29,7 @@ struct ShareEventHeader {
    unsigned int evtCoreStatusFlag;
    char token[maxTokenLength];
 };
+} // anonymous namespace
 
 //___________________________________________________________________________
 AthenaSharedMemoryTool::AthenaSharedMemoryTool(const std::string& type,
diff --git a/Control/AthenaIPCTools/src/AthenaYamplTool.cxx b/Control/AthenaIPCTools/src/AthenaYamplTool.cxx
index 8de2200c2c57ea9a28439a3b4666da7a4f2c7c87..65e28aa56f70bc90f7a017277c6ecc5c71afa5b6 100644
--- a/Control/AthenaIPCTools/src/AthenaYamplTool.cxx
+++ b/Control/AthenaIPCTools/src/AthenaYamplTool.cxx
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2021 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2022 CERN for the benefit of the ATLAS collaboration
 */
 
 #include "AthenaYamplTool.h"
@@ -12,6 +12,7 @@
 #include "yampl/SocketFactory.h"
 #include <sstream>
 
+namespace {
 struct ShareEventHeader {
    long evtSeqNumber;
    long fileSeqNumber;
@@ -21,6 +22,7 @@ struct ShareEventHeader {
    uint32_t evtTerm1;
    uint32_t evtTerm2;
 };
+} // anonymous namespace
 
 //___________________________________________________________________________
 AthenaYamplTool::AthenaYamplTool(const std::string& type,