Index: Imath-3.1.3/docs/CMakeLists.txt
===================================================================
--- Imath-3.1.3.orig/docs/CMakeLists.txt
+++ Imath-3.1.3/docs/CMakeLists.txt
@@ -42,6 +42,8 @@ add_custom_command(OUTPUT ${SPHINX_INDEX
 add_custom_target(Sphinx ALL DEPENDS ${SPHINX_INDEX_FILE})
 
 # Add an install target to install the docs
-include(GNUInstallDirs)
-install(DIRECTORY ${SPHINX_BUILD}
-DESTINATION ${CMAKE_INSTALL_DOCDIR})
+if(INSTALL_DOCS)
+    include(GNUInstallDirs)
+    install(DIRECTORY ${SPHINX_BUILD}
+    DESTINATION ${CMAKE_INSTALL_DOCDIR})
+endif()
Index: Imath-3.1.3/CMakeLists.txt
===================================================================
--- Imath-3.1.3.orig/CMakeLists.txt
+++ Imath-3.1.3/CMakeLists.txt
@@ -75,6 +75,7 @@ endif()
 
 option(DOCS "Set ON to build html documentation")
 if (DOCS)
+  option(INSTALL_DOCS "Set ON to install html documentation" ON)
   add_subdirectory(docs)
 endif()