diff --git a/CHANGELOG b/CHANGELOG
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,8 @@
+2.10 (Changes from 2.9.0)
+=========================
+* Removed unused depencencies
+* Fixed bug in the definition of nullPL
+
 2.9.0 (Changes from 2.0.3)
 ==========================
 * Introduced partial/nullable lenses (Data.Lens.Partial).
diff --git a/data-lens.cabal b/data-lens.cabal
--- a/data-lens.cabal
+++ b/data-lens.cabal
@@ -1,6 +1,6 @@
 name:               data-lens
 category:           Control, Comonads
-version:            2.9.0
+version:            2.10.0
 license:            BSD3
 cabal-version:      >= 1.6
 license-file:       LICENSE
@@ -24,12 +24,10 @@
 
 library
   build-depends:
-    base >= 4 && < 5,
+    base                 >= 4       && < 5,
     comonad              >= 1.1.1.3 && < 1.2,
-    comonad-transformers >= 2.1     && < 2.2,
+    comonad-transformers >= 2.0     && < 2.2,
     containers           >= 0.3     && < 0.5,
-    contravariant        >= 0.2.0.1 && < 0.3,
-    distributive         >= 0.2.1   && < 0.3,
     semigroupoids        >= 1.2.4   && < 1.4,
     transformers         >= 0.2.0   && < 0.4
 
diff --git a/src/Data/Lens/Partial/Common.hs b/src/Data/Lens/Partial/Common.hs
--- a/src/Data/Lens/Partial/Common.hs
+++ b/src/Data/Lens/Partial/Common.hs
@@ -51,7 +51,7 @@
 
 -- If the Partial is null.
 nullPL :: PartialLens a b -> a -> Bool
-nullPL l = isJust . getPL l
+nullPL l = isNothing . getPL l
 
 getorEmptyPL :: (Monoid o) => PartialLens a b -> (b -> o) -> a -> o
 getorEmptyPL l p = maybe mempty p . getPL l