diff --git a/src/GF/Compile/GenerateFCFG.hs b/src/GF/Compile/GenerateFCFG.hs
index 26fd2a4d9..bb8ba9452 100644
--- a/src/GF/Compile/GenerateFCFG.hs
+++ b/src/GF/Compile/GenerateFCFG.hs
@@ -329,6 +329,7 @@ getParserInfo :: GrammarEnv -> ParserInfo
 getParserInfo (GrammarEnv last_id catSet seqSet funSet prodSet) =
   ParserInfo { functions   = mkArray funSet
              , sequences   = mkArray seqSet
+	     , productions0= prodSet
 	     , productions = prodSet
 	     , startCats   = Map.map getFCatList catSet
 	     , totalCats   = last_id+1
diff --git a/src/GF/Compile/GeneratePMCFG.hs b/src/GF/Compile/GeneratePMCFG.hs
index e29fce754..bb3215102 100644
--- a/src/GF/Compile/GeneratePMCFG.hs
+++ b/src/GF/Compile/GeneratePMCFG.hs
@@ -405,13 +405,15 @@ getParserInfo :: GrammarEnv -> ParserInfo
 getParserInfo (GrammarEnv last_id catSet seqSet funSet crcSet prodSet) =
   ParserInfo { functions   = mkArray funSet
              , sequences   = mkArray seqSet
-	     , productions = IntMap.union prodSet coercions
+	     , productions0= productions0
+	     , productions = filterProductions productions0
 	     , startCats   = maybe Map.empty (Map.map (\(start,end,_) -> range (start,end))) (IntMap.lookup 0 catSet)
 	     , totalCats   = last_id+1
 	     }
   where
     mkArray map = array (0,Map.size map-1) [(v,k) | (k,v) <- Map.toList map]
     
+    productions0 = IntMap.union prodSet coercions
     coercions = IntMap.fromList [(fcat,Set.fromList (map FCoerce sub_fcats)) | (sub_fcats,fcat) <- Map.toList crcSet]
 
 getFCats :: GrammarEnv -> ProtoFCat -> [FCat]
diff --git a/src/PGF/Binary.hs b/src/PGF/Binary.hs
index acbff2309..9df9be146 100644
--- a/src/PGF/Binary.hs
+++ b/src/PGF/Binary.hs
@@ -7,6 +7,8 @@ import Data.Binary.Put
 import Data.Binary.Get
 import qualified Data.ByteString as BS
 import qualified Data.Map as Map
+import qualified Data.IntMap as IntMap
+import qualified Data.Set as Set
 import Control.Monad
 
 pgfMajorVersion, pgfMinorVersion :: Word16
@@ -159,13 +161,15 @@ instance Binary Production where
              _ -> decodingError
 
 instance Binary ParserInfo where
-  put p = put (functions p, sequences p, productions p, totalCats p, startCats p)
+  put p = put (functions p, sequences p, productions0 p, totalCats p, startCats p)
   get = do functions   <- get
            sequences   <- get
-           productions <- get
+           productions0<- get
            totalCats   <- get
            startCats   <- get
-           return (ParserInfo{functions=functions,sequences=sequences,productions=productions
+           return (ParserInfo{functions=functions,sequences=sequences
+                             ,productions0=productions0
+                             ,productions =filterProductions productions0
                              ,totalCats=totalCats,startCats=startCats})
 
 decodingError = fail "This PGF file was compiled with different version of GF"
diff --git a/src/PGF/PMCFG.hs b/src/PGF/PMCFG.hs
index 3196674ee..9a0dfa98e 100644
--- a/src/PGF/PMCFG.hs
+++ b/src/PGF/PMCFG.hs
@@ -41,7 +41,8 @@ data Alternative =
 data ParserInfo
     = ParserInfo { functions   :: Array FunId FFun
                  , sequences   :: Array SeqId FSeq
-	         , productions :: IntMap.IntMap (Set.Set Production)
+	         , productions0:: IntMap.IntMap (Set.Set Production)    -- this are the original productions as they are loaded from the PGF file
+	         , productions :: IntMap.IntMap (Set.Set Production)    -- this are the productions after the filtering for useless productions
 	         , startCats   :: Map.Map CId [FCat]
 	         , totalCats   :: {-# UNPACK #-} !FCat
 	         }
@@ -57,7 +58,7 @@ fcatVar    = (-4)
 ppPMCFG :: ParserInfo -> Doc
 ppPMCFG pinfo =
   text "productions" $$
-  nest 2 (vcat [ppProduction (fcat,prod) | (fcat,set) <- IntMap.toList (productions pinfo), prod <- Set.toList set]) $$
+  nest 2 (vcat [ppProduction (fcat,prod) | (fcat,set) <- IntMap.toList (productions0 pinfo), prod <- Set.toList set]) $$
   text "functions" $$
   nest 2 (vcat (map ppFun (assocs (functions pinfo)))) $$
   text "sequences" $$
@@ -101,3 +102,11 @@ ppFCat  fcat
 
 ppFunId funid = char 'F' <> int funid
 ppSeqId seqid = char 'S' <> int seqid
+
+
+filterProductions prods =
+  fmap (Set.filter filterRule) prods
+  where
+    filterRule (FApply funid args) = all (\fcat -> IntMap.member fcat prods) args
+    filterRule (FCoerce _)         = True
+    filterRule _                   = True