diff --git a/src/Language/Haskell/TH/ReifyMany/Internal.hs b/src/Language/Haskell/TH/ReifyMany/Internal.hs
--- a/src/Language/Haskell/TH/ReifyMany/Internal.hs
+++ b/src/Language/Haskell/TH/ReifyMany/Internal.hs
@@ -100,7 +100,7 @@
 -- the given 'TypeclassInstance'.
 instanceMatches :: TypeclassInstance -> Name -> Bool
 instanceMatches (TypeclassInstance _ typ _) n' =
-    case tailMay $ map (headMay . unAppsT) $ unAppsT typ of
+    case tailMay $ map (fmap unSigT . headMay . unAppsT) $ unAppsT typ of
         Nothing -> False
         Just xs -> not $ null [() | Just (ConT n) <- xs, n == n']
 
@@ -110,3 +110,8 @@
   where
     go xs (AppT l x) = go (x : xs) l
     go xs ty = ty : xs
+
+-- | Remove any explicit kind signatures (i.e., 'SigT's) from a 'Type'.
+unSigT :: Type -> Type
+unSigT (SigT t _) = unSigT t
+unSigT t          = t
diff --git a/th-reify-many.cabal b/th-reify-many.cabal
--- a/th-reify-many.cabal
+++ b/th-reify-many.cabal
@@ -1,5 +1,5 @@
 name:              th-reify-many
-version:           0.1.8
+version:           0.1.9
 synopsis:          Recurseively reify template haskell datatype info
 
 description:       @th-reify-many@ provides functions for recursively reifying top