diff --git a/ecal/core/CMakeLists.txt b/ecal/core/CMakeLists.txt
index 3c7d57189..775f8a7c8 100644
--- a/ecal/core/CMakeLists.txt
+++ b/ecal/core/CMakeLists.txt
@@ -397,7 +397,7 @@ set(ecal_header_base
     ${ecal_header_msg}
 )
 
-ecal_add_ecal_shared_library(${PROJECT_NAME} 
+ecal_add_library(${PROJECT_NAME} 
     ${ecal_custom_tclap_cpp_src}
     ${ecal_io_cpp_src} 
     ${ecal_io_mem_cpp_src} 
@@ -433,7 +433,7 @@ if(UNIX)
   set_source_files_properties(src/convert_utf.cpp PROPERTIES COMPILE_FLAGS -Wno-implicit-fallthrough)
 endif()
 
-ecal_add_ecal_shared_library(${PROJECT_NAME}_c ${ecal_c_src} ${ecal_c_win_src})
+ecal_add_library(${PROJECT_NAME}_c ${ecal_c_src} ${ecal_c_win_src})
 
 add_library(eCAL::${PROJECT_NAME}   ALIAS ${PROJECT_NAME})
 add_library(eCAL::${PROJECT_NAME}_c ALIAS ${PROJECT_NAME}_c)
@@ -457,6 +457,11 @@ target_compile_definitions(${PROJECT_NAME}
     $<$<BOOL:${ECAL_HAS_ROBUST_MUTEX}>:ECAL_HAS_ROBUST_MUTEX>
     $<$<BOOL:${ECAL_USE_CLOCKLOCK_MUTEX}>:ECAL_USE_CLOCKLOCK_MUTEX>)
 
+if(BUILD_SHARED_LIBS)
+  target_compile_definitions(${PROJECT_NAME}_c PUBLIC eCAL_SHARED_LIB)
+  target_compile_definitions(${PROJECT_NAME}   PUBLIC eCAL_SHARED_LIB)
+endif()
+
 if(ECAL_NPCAP_SUPPORT)
   target_compile_definitions(${PROJECT_NAME}
     PRIVATE ECAL_NPCAP_SUPPORT)
@@ -507,8 +512,8 @@ target_include_directories(${PROJECT_NAME} PRIVATE ${SIMPLEINI_INCLUDE_DIRS})
 set_property(TARGET ${PROJECT_NAME}   PROPERTY FOLDER ecal/core)
 set_property(TARGET ${PROJECT_NAME}_c PROPERTY FOLDER ecal/core)
 
-ecal_install_ecal_shared_library(${PROJECT_NAME}_c)
-ecal_install_ecal_shared_library(${PROJECT_NAME})
+ecal_install_ecal_library(${PROJECT_NAME}_c)
+ecal_install_ecal_library(${PROJECT_NAME})
 
 install(DIRECTORY
    "include/" DESTINATION "${INSTALL_INCLUDE_DIR}" COMPONENT sdk
diff --git a/ecal/core/include/ecal/ecal_os.h b/ecal/core/include/ecal/ecal_os.h
index a962036f2..5d466cc86 100644
--- a/ecal/core/include/ecal/ecal_os.h
+++ b/ecal/core/include/ecal/ecal_os.h
@@ -47,7 +47,7 @@
 #define ECAL_OS_FREEBSD
 #endif
 
-#ifdef _MSC_VER
+#if defined(_MSC_VER) && defined(eCAL_SHARED_LIB)
   #ifdef eCAL_EXPORTS
     #define ECALC_API __declspec(dllexport)
   #else /* eCAL_EXPORTS */
@@ -64,11 +64,15 @@
 #endif
 
 #ifdef _MSC_VER
+  #ifdef eCAL_SHARED_LIB
   #ifdef eCAL_EXPORTS
     #define ECALC_API_DEPRECATED __declspec(dllexport deprecated)
   #else /* eCAL_EXPORTS */
     #define ECALC_API_DEPRECATED __declspec(dllimport deprecated)
   #endif /* eCAL_EXPORTS */
+  #else
+    #define ECALC_API_DEPRECATED  
+  #endif
 #elif defined(__GNUC__) || defined(__clang__)
   #define ECALC_API_DEPRECATED __attribute__((deprecated))
 #else