diff -Naur ORIG/CMakeLists.txt PATCHED/CMakeLists.txt
--- ORIG/CMakeLists.txt	2026-03-30 08:55:14.791601845 +0000
+++ PATCHED/CMakeLists.txt	2026-03-30 08:55:14.791601845 +0000
@@ -1,6 +1,7 @@
 cmake_minimum_required (VERSION 3.13)
 enable_language(Fortran)
 project (mcfm C CXX Fortran)
+include("GNUInstallDirs")
 
 if (CMAKE_Fortran_COMPILER_ID STREQUAL "GNU")
     set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS} -cpp -finit-local-zero -ffixed-line-length-none -ffree-line-length-512 -fopenmp -ffpe-summary=none")
@@ -63,7 +64,7 @@
     SOURCE_DIR ${CMAKE_BINARY_DIR}/lib/qcdloop-2.0.9
     BUILD_IN_SOURCE ON
     PATCH_COMMAND mkdir -p ${CMAKE_BINARY_DIR}/local
-    CMAKE_ARGS -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE} -DENABLE_FORTRAN_WRAPPER=ON -DCMAKE_INSTALL_PREFIX=${CMAKE_BINARY_DIR}/local -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER} -DCMAKE_C_COMPILER=${CMAKE_C_COMPILER} -DCMAKE_INSTALL_LIBDIR=lib
+    CMAKE_ARGS  -DCMAKE_POLICY_VERSION_MINIMUM=3.5 -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE} -DENABLE_FORTRAN_WRAPPER=ON -DCMAKE_INSTALL_PREFIX=${CMAKE_BINARY_DIR}/local -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER} -DCMAKE_C_COMPILER=${CMAKE_C_COMPILER} -DCMAKE_INSTALL_LIBDIR=lib
     BUILD_COMMAND ${MAKE}
     INSTALL_COMMAND ${CMAKE_MAKE_PROGRAM} install
 )
@@ -73,7 +74,7 @@
     PREFIX ${CMAKE_BINARY_DIR}/lib/oneloop
     SOURCE_DIR ${CMAKE_BINARY_DIR}/lib/oneloop
     BUILD_IN_SOURCE ON
-    CMAKE_ARGS -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE} -DCMAKE_Fortran_COMPILER=${CMAKE_Fortran_COMPILER} -DCMAKE_Fortran_FLAGS=-fPIC
+    CMAKE_ARGS -DCMAKE_POLICY_VERSION_MINIMUM=3.5 -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE} -DCMAKE_Fortran_COMPILER=${CMAKE_Fortran_COMPILER} -DCMAKE_Fortran_FLAGS=-fPIC
     BUILD_COMMAND ${MAKE}
     INSTALL_COMMAND mkdir -p ${CMAKE_BINARY_DIR}/local/include && cp ${CMAKE_BINARY_DIR}/lib/oneloop/avh_olo.mod ${CMAKE_BINARY_DIR}/local/include 
 )
@@ -99,6 +100,7 @@
 
 option(with_vvamp "Build with VVAmp for WW,WZ and ZZ processes" ON)
 
+include_directories(${CMAKE_BINARY_DIR}/local/include/qd ${CMAKE_BINARY_DIR}/local/include)
 string(ASCII 27 Esc)
 set(BoldRed "${Esc}[1;31m")
 set(ColorReset "${Esc}[m")
@@ -167,6 +169,7 @@
        target_include_directories(mltest2 PRIVATE src/Inc)
        target_compile_definitions(mltest2 PUBLIC LIB_SUFFIX="${CMAKE_SHARED_LIBRARY_SUFFIX}")
     endif()
+    install(TARGETS libmcfm DESTINATION ${CMAKE_INSTALL_LIBDIR})
 endif()
 
 add_subdirectory(src)
@@ -334,10 +337,14 @@
 
 ## Installation
 
-install(FILES "${CMAKE_SOURCE_DIR}/Bin/process.DAT" DESTINATION "${CMAKE_BINARY_DIR}")
-install(FILES "${CMAKE_SOURCE_DIR}/Bin/br.sm1" DESTINATION "${CMAKE_BINARY_DIR}")
-install(FILES "${CMAKE_SOURCE_DIR}/Bin/br.sm2" DESTINATION "${CMAKE_BINARY_DIR}")
-install(DIRECTORY "${CMAKE_SOURCE_DIR}/Bin/PDFs" DESTINATION "${CMAKE_BINARY_DIR}")
+install(TARGETS mcfm DESTINATION ${CMAKE_INSTALL_BINDIR})
+install(FILES "${CMAKE_SOURCE_DIR}/Bin/process.DAT" DESTINATION ${CMAKE_INSTALL_BINDIR})
+install(FILES "${CMAKE_SOURCE_DIR}/Bin/br.sm1" DESTINATION ${CMAKE_INSTALL_BINDIR})
+install(FILES "${CMAKE_SOURCE_DIR}/Bin/br.sm2" DESTINATION ${CMAKE_INSTALL_BINDIR})
+install(DIRECTORY "${CMAKE_SOURCE_DIR}/src/Inc/MCFM" DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})
+if(use_internal_lhapdf)
+  install(DIRECTORY "${CMAKE_SOURCE_DIR}/Bin/PDFs" DESTINATION "${CMAKE_BINARY_DIR}")
+endif()
 
 if(${with_library})
     if ((DEFINED OLDIR) OR (DEFINED RCLDIR) OR (DEFINED MLDIR))
