diff --git a/src/Network/Minio/PutObject.hs b/src/Network/Minio/PutObject.hs
index 3cf9183..d5c00b5 100644
--- a/src/Network/Minio/PutObject.hs
+++ b/src/Network/Minio/PutObject.hs
@@ -25,21 +25,16 @@ module Network.Minio.PutObject
   ) where
 
 
-import qualified Data.ByteString as B
 import qualified Data.Conduit as C
-import           Data.Conduit.Binary (sourceHandleRange)
 import qualified Data.Conduit.Binary as CB
 import qualified Data.Conduit.Combinators as CC
 import qualified Data.Conduit.List as CL
 import qualified Data.List as List
-import qualified Data.Map.Strict as Map
 
 import           Lib.Prelude
 
 import           Network.Minio.Data
-import           Network.Minio.Data.Crypto
 import           Network.Minio.Errors
-import           Network.Minio.ListOps
 import           Network.Minio.S3API
 import           Network.Minio.Utils
 
@@ -117,35 +112,17 @@ selectPartSizes size = uncurry (List.zip3 [1..]) $
       | st + m >= sz = [(st, sz - st)]
       | otherwise = (st, m) : loop (st + m) sz
 
--- returns partinfo if part is already uploaded.
-checkUploadNeeded :: Payload -> PartNumber
-                  -> Map.Map PartNumber ObjectPartInfo
-                  -> Minio (Maybe PartTuple)
-checkUploadNeeded payload n pmap = do
-  (md5hash, pSize) <- case payload of
-    PayloadBS bs -> return (hashMD5 bs, fromIntegral $ B.length bs)
-    PayloadH h off size -> fmap (, size) $
-      hashMD5FromSource $ sourceHandleRange h (Just $ fromIntegral off)
-      (Just $ fromIntegral size)
-  case Map.lookup n pmap of
-    Nothing -> return Nothing
-    Just (ObjectPartInfo _ etag size _) -> return $
-      bool Nothing (Just (n, etag)) $
-      md5hash == encodeUtf8 etag && size == pSize
-
 parallelMultipartUpload :: Bucket -> Object -> FilePath -> Int64
                         -> Minio ETag
 parallelMultipartUpload b o filePath size = do
-  (uidMay, pmap) <- getExistingUpload b o
-
-  -- get a new upload id if needed.
-  uploadId <- maybe (newMultipartUpload b o []) return uidMay
+  -- get a new upload id.
+  uploadId <- newMultipartUpload b o []
 
   let partSizeInfo = selectPartSizes size
 
   -- perform upload with 10 threads
   uploadedPartsE <- limitedMapConcurrently 10
-                    (uploadPart pmap uploadId) partSizeInfo
+                    (uploadPart uploadId) partSizeInfo
 
   -- if there were any errors, rethrow exception.
   mapM_ throwM $ lefts uploadedPartsE
@@ -153,22 +130,17 @@ parallelMultipartUpload b o filePath size = do
   -- if we get here, all parts were successfully uploaded.
   completeMultipartUpload b o uploadId $ rights uploadedPartsE
   where
-    uploadPart pmap uploadId (partNum, offset, sz) =
+    uploadPart uploadId (partNum, offset, sz) =
       withNewHandle filePath $ \h -> do
         let payload = PayloadH h offset sz
-        pInfoMay <- checkUploadNeeded payload partNum pmap
-        maybe
-          (putObjectPart b o uploadId partNum [] payload)
-          return pInfoMay
+        putObjectPart b o uploadId partNum [] payload
 
 -- | Upload multipart object from conduit source sequentially
 sequentialMultipartUpload :: Bucket -> Object -> Maybe Int64
                           -> C.Producer Minio ByteString -> Minio ETag
 sequentialMultipartUpload b o sizeMay src = do
-  (uidMay, pmap) <- getExistingUpload b o
-
-  -- get a new upload id if needed.
-  uploadId <- maybe (newMultipartUpload b o []) return uidMay
+  -- get a new upload id.
+  uploadId <- newMultipartUpload b o []
 
   -- upload parts in loop
   let partSizes = selectPartSizes $ maybe maxObjectSize identity sizeMay
@@ -176,35 +148,21 @@ sequentialMultipartUpload b o sizeMay src = do
   uploadedParts <- src
               C..| chunkBSConduit sizes
               C..| CL.map PayloadBS
-              C..| checkAndUpload uploadId pmap pnums
+              C..| uploadPart' uploadId pnums
               C.$$ CC.sinkList
 
   -- complete multipart upload
   completeMultipartUpload b o uploadId uploadedParts
 
   where
-    checkAndUpload _ _ [] = return ()
-    checkAndUpload uid pmap (pn:pns) = do
+    uploadPart' _ [] = return ()
+    uploadPart' uid (pn:pns) = do
       payloadMay <- C.await
       case payloadMay of
         Nothing -> return ()
-        Just payload -> do partMay <- lift $ checkUploadNeeded payload pn pmap
-                           pinfo <- maybe
-                                    (lift $ putObjectPart b o uid pn [] payload)
-                                    return partMay
+        Just payload -> do pinfo <- lift $ putObjectPart b o uid pn [] payload
                            C.yield pinfo
-                           checkAndUpload uid pmap pns
-
--- | Looks for incomplete uploads for an object. Returns the first one
--- if there are many.
-getExistingUpload :: Bucket -> Object
-                  -> Minio (Maybe UploadId, Map.Map PartNumber ObjectPartInfo)
-getExistingUpload b o = do
-  uidMay <- (fmap . fmap) uiUploadId $
-            listIncompleteUploads b (Just o) False C.$$ CC.head
-  parts <- maybe (return [])
-    (\uid -> listIncompleteParts b o uid C.$$ CC.sinkList) uidMay
-  return (uidMay, Map.fromList $ map (\p -> (opiNumber p, p)) parts)
+                           uploadPart' uid pns
 
 -- | Copy an object using single or multipart copy strategy.
 copyObjectInternal :: Bucket -> Object -> CopyPartSource