diff --git a/mumps.spec b/mumps.spec
index 0dd580a..834b4fa 100644
--- a/mumps.spec
+++ b/mumps.spec
@@ -217,6 +217,7 @@ BuildRequires:  scotch-devel
 BuildRequires:  libmumps%{?so_ver}
 BuildRequires:  %{pname}-devel
 BuildRequires:  %{pname}-devel-static
+# Needed for non-HPC MPI builds to link to it from the MPI libdir - see below.
 BuildRequires:  libmumps-scotch%{?so_ver}
 BuildRequires:  %{pname}-scotch-devel
 BuildRequires:  %{pname}-scotch-devel-static