diff --git a/cms/patatrack/traces/cms.cern.ch_spec_custom.txt b/cms/patatrack/traces/cms.cern.ch_spec_custom.txt
new file mode 100644
index 0000000000000000000000000000000000000000..e1badbcfe7e2791c18c36773c0a3321a621e3366
--- /dev/null
+++ b/cms/patatrack/traces/cms.cern.ch_spec_custom.txt
@@ -0,0 +1,3 @@
+/slc7_amd64_gcc820/external/py2-future/*
+/slc7_amd64_gcc820/external/py2-numpy/*
+/slc7_amd64_gcc820/external/py2-scipy/*
\ No newline at end of file