diff --git a/Data/Array/Base.hs b/Data/Array/Base.hs
index e00a97dbd626548210ce9e9231a51a288983fac5..d632e105d4f5e37466f2a492f9649c8b66802dad 100644
--- a/Data/Array/Base.hs
+++ b/Data/Array/Base.hs
@@ -1390,7 +1390,7 @@ freeze marr = do
   -- use the safe array creation function here.
   return (listArray (l,u) es)
 
-freezeSTUArray :: Ix i => STUArray s i e -> ST s (UArray i e)
+freezeSTUArray :: STUArray s i e -> ST s (UArray i e)
 freezeSTUArray (STUArray l u n marr#) = ST $ \s1# ->
     case sizeofMutableByteArray# marr#  of { n# ->
     case newByteArray# n# s1#           of { (# s2#, marr'# #) ->
@@ -1465,7 +1465,7 @@ thaw arr = case bounds arr of
               | i <- [0 .. n - 1]]
     return marr
 
-thawSTUArray :: Ix i => UArray i e -> ST s (STUArray s i e)
+thawSTUArray :: UArray i e -> ST s (STUArray s i e)
 thawSTUArray (UArray l u n arr#) = ST $ \s1# ->
     case sizeofByteArray# arr#          of { n# ->
     case newByteArray# n# s1#           of { (# s2#, marr# #) ->
@@ -1525,7 +1525,7 @@ unsafeThaw :: (Ix i, IArray a e, MArray b e m) => a i e -> m (b i e)
 unsafeThaw = thaw
 
 {-# INLINE unsafeThawSTUArray #-}
-unsafeThawSTUArray :: Ix i => UArray i e -> ST s (STUArray s i e)
+unsafeThawSTUArray :: UArray i e -> ST s (STUArray s i e)
 unsafeThawSTUArray (UArray l u n marr#) =
     return (STUArray l u n (unsafeCoerce# marr#))
 
@@ -1535,7 +1535,7 @@ unsafeThawSTUArray (UArray l u n marr#) =
     #-}
 
 {-# INLINE unsafeThawIOArray #-}
-unsafeThawIOArray :: Ix ix => Arr.Array ix e -> IO (IOArray ix e)
+unsafeThawIOArray :: Arr.Array ix e -> IO (IOArray ix e)
 unsafeThawIOArray arr = stToIO $ do
     marr <- ArrST.unsafeThawSTArray arr
     return (IOArray marr)
@@ -1544,7 +1544,7 @@ unsafeThawIOArray arr = stToIO $ do
 "unsafeThaw/IOArray"  unsafeThaw = unsafeThawIOArray
     #-}
 
-thawIOArray :: Ix ix => Arr.Array ix e -> IO (IOArray ix e)
+thawIOArray :: Arr.Array ix e -> IO (IOArray ix e)
 thawIOArray arr = stToIO $ do
     marr <- ArrST.thawSTArray arr
     return (IOArray marr)
@@ -1553,7 +1553,7 @@ thawIOArray arr = stToIO $ do
 "thaw/IOArray"  thaw = thawIOArray
     #-}
 
-freezeIOArray :: Ix ix => IOArray ix e -> IO (Arr.Array ix e)
+freezeIOArray :: IOArray ix e -> IO (Arr.Array ix e)
 freezeIOArray (IOArray marr) = stToIO (ArrST.freezeSTArray marr)
 
 {-# RULES
@@ -1561,7 +1561,7 @@ freezeIOArray (IOArray marr) = stToIO (ArrST.freezeSTArray marr)
     #-}
 
 {-# INLINE unsafeFreezeIOArray #-}
-unsafeFreezeIOArray :: Ix ix => IOArray ix e -> IO (Arr.Array ix e)
+unsafeFreezeIOArray :: IOArray ix e -> IO (Arr.Array ix e)
 unsafeFreezeIOArray (IOArray marr) = stToIO (ArrST.unsafeFreezeSTArray marr)
 
 {-# RULES
diff --git a/Data/Array/IO/Internals.hs b/Data/Array/IO/Internals.hs
index 1a015d988cfa9309ed433190e0f06fc840c26558..6c91d7c173eff700d605ca5bedcf86b6b96b80f9 100644
--- a/Data/Array/IO/Internals.hs
+++ b/Data/Array/IO/Internals.hs
@@ -375,7 +375,7 @@ castIOUArray (IOUArray marr) = stToIO $ do
     return (IOUArray marr')
 
 {-# INLINE unsafeThawIOUArray #-}
-unsafeThawIOUArray :: Ix ix => UArray ix e -> IO (IOUArray ix e)
+unsafeThawIOUArray :: UArray ix e -> IO (IOUArray ix e)
 unsafeThawIOUArray arr = stToIO $ do
     marr <- unsafeThawSTUArray arr
     return (IOUArray marr)
@@ -384,7 +384,7 @@ unsafeThawIOUArray arr = stToIO $ do
 "unsafeThaw/IOUArray" unsafeThaw = unsafeThawIOUArray
     #-}
 
-thawIOUArray :: Ix ix => UArray ix e -> IO (IOUArray ix e)
+thawIOUArray :: UArray ix e -> IO (IOUArray ix e)
 thawIOUArray arr = stToIO $ do
     marr <- thawSTUArray arr
     return (IOUArray marr)
@@ -394,14 +394,14 @@ thawIOUArray arr = stToIO $ do
     #-}
 
 {-# INLINE unsafeFreezeIOUArray #-}
-unsafeFreezeIOUArray :: Ix ix => IOUArray ix e -> IO (UArray ix e)
+unsafeFreezeIOUArray :: IOUArray ix e -> IO (UArray ix e)
 unsafeFreezeIOUArray (IOUArray marr) = stToIO (unsafeFreezeSTUArray marr)
 
 {-# RULES
 "unsafeFreeze/IOUArray" unsafeFreeze = unsafeFreezeIOUArray
     #-}
 
-freezeIOUArray :: Ix ix => IOUArray ix e -> IO (UArray ix e)
+freezeIOUArray :: IOUArray ix e -> IO (UArray ix e)
 freezeIOUArray (IOUArray marr) = stToIO (freezeSTUArray marr)
 
 {-# RULES
diff --git a/Data/Array/ST.hs b/Data/Array/ST.hs
index 29bfafbe7c7f7e4f57fda41494916533580313c0..31e1ed0cb7ab05a08b2350e0226904c41350c75b 100644
--- a/Data/Array/ST.hs
+++ b/Data/Array/ST.hs
@@ -37,8 +37,7 @@ import GHC.Arr          ( STArray, Array, unsafeFreezeSTArray )
 -- the array before returning it - it uses 'unsafeFreeze' internally, but
 -- this wrapper is a safe interface to that function.
 --
-runSTArray :: (Ix i)
-           => (forall s . ST s (STArray s i e))
+runSTArray :: (forall s . ST s (STArray s i e))
            -> Array i e
 runSTArray st = runST (st >>= unsafeFreezeSTArray)
 
@@ -48,9 +47,8 @@ runSTArray st = runST (st >>= unsafeFreezeSTArray)
 -- 'unsafeFreeze' internally, but this wrapper is a safe interface to
 -- that function.
 --
-runSTUArray :: (Ix i)
-           => (forall s . ST s (STUArray s i e))
-           -> UArray i e
+runSTUArray :: (forall s . ST s (STUArray s i e))
+            -> UArray i e
 runSTUArray st = runST (st >>= unsafeFreezeSTUArray)