diff --git a/testsuite/tests/rts/all.T b/testsuite/tests/rts/all.T
index 35f97e5f77c628846973bad036f14f552e1582b1..4acaa4c43d47ee5b455bfcd903c8c7b4703082e9 100644
--- a/testsuite/tests/rts/all.T
+++ b/testsuite/tests/rts/all.T
@@ -216,10 +216,6 @@ test('EventlogOutput_IPE',
      ],
      makefile_test, ['EventlogOutput_IPE'])
 
-# Remove the capability prefix from IPE event log lines.
-def noCapabilityOutputFilter(s):
-     return re.sub(r'[a-f0-9]+: IPE:', 'IPE:', s)
-
 test('T4059', req_c, makefile_test, ['T4059'])
 
 # Test for #4274
diff --git a/testsuite/tests/rts/ipe/all.T b/testsuite/tests/rts/ipe/all.T
index acb7e1f3b90b1dfe2ebb1c39b2829bb98f1ad625..b0d680beed2def68b81518670c950423a04f55c2 100644
--- a/testsuite/tests/rts/ipe/all.T
+++ b/testsuite/tests/rts/ipe/all.T
@@ -1,3 +1,7 @@
+# Remove the capability prefix from IPE event log lines.
+def noCapabilityOutputFilter(s):
+     return re.sub(r'[a-f0-9]+: IPE:', 'IPE:', s)
+
 test('ipeMap', [extra_files(['ipe_lib.c', 'ipe_lib.h']), c_src, omit_ghci], compile_and_run, ['ipe_lib.c'])
 
 # Manually create IPE entries and dump them to event log (stderr).
@@ -30,4 +34,3 @@ test('ipeEventLog_fromMap',
        when(opsys('darwin'), fragile(0))
      ],
      compile_and_run, ['ipe_lib.c'])
-