diff --git a/src/Compiler/Optimize/InnerLambdasToTopLevelFuncs.fs b/src/Compiler/Optimize/InnerLambdasToTopLevelFuncs.fs
index 071fc474a18..74ee68565e2 100644
--- a/src/Compiler/Optimize/InnerLambdasToTopLevelFuncs.fs
+++ b/src/Compiler/Optimize/InnerLambdasToTopLevelFuncs.fs
@@ -194,12 +194,10 @@ module Pass1_DetermineTLRAndArities =
             let nFormals = vss.Length
             let nMaxApplied = GetMaxNumArgsAtUses xinfo f
             let arity = Operators.min nFormals nMaxApplied
-            if atTopLevel then
-                Some (f, arity)
-            else if arity<>0 || not (isNil tps) then
-                Some (f, arity)
-            else
-                None
+            if atTopLevel then Some (f, arity)
+            elif g.realsig && arity > 0 then None                   // This needs some investigation I sorta understand but would have a hard time explaining it
+            elif arity<>0 || not (isNil tps) then Some (f, arity)
+            else None
 
     /// Check if f involves any value recursion (so can skip those).
     /// ValRec considered: recursive && some f in mutual binding is not bound to a lambda