diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,9 @@
+50200.1.3
+=========
+
+API changes:
+ * The `PostProps` type got support for the `from_webhook` prop
+
 50200.1.2
 =========
 
diff --git a/mattermost-api.cabal b/mattermost-api.cabal
--- a/mattermost-api.cabal
+++ b/mattermost-api.cabal
@@ -1,7 +1,14 @@
 name:                mattermost-api
-version:             50200.1.2
+version:             50200.1.3
 synopsis:            Client API for Mattermost chat system
-description:         Client API for Mattermost chat system
+
+description:         Client API for Mattermost chat system.  Mattermost is a
+                     flexible, open source messaging platform that
+                     meets even the most demanding privacy and
+                     security standards.  This library provides
+                     network API interaction with the Mattermost
+                     server.
+
 license:             BSD3
 license-file:        LICENSE
 author:              Jason Dagit
@@ -11,7 +18,7 @@
 build-type:          Simple
 extra-doc-files:     README.md,
                      CHANGELOG.md
-cabal-version:       >=1.18
+cabal-version:       1.18
 tested-with:         GHC == 7.10.3, GHC == 8.0.1
 source-repository    head
   type: git
diff --git a/src/Network/Mattermost/Endpoints.hs b/src/Network/Mattermost/Endpoints.hs
--- a/src/Network/Mattermost/Endpoints.hs
+++ b/src/Network/Mattermost/Endpoints.hs
@@ -7,7 +7,7 @@
 import qualified Data.Aeson as A
 import qualified Data.ByteString.Char8 as B
 import qualified Data.HashMap.Strict as HM
-import           Data.Sequence (Seq)
+import           Data.Sequence (Seq, fromList)
 import           Data.Text (Text)
 import qualified Data.Text as T
 import qualified Network.HTTP.Base as HTTP
@@ -3269,14 +3269,14 @@
 -- --
 
 data UploadResponse = UploadResponse
-  { uploadResponseClientIds :: (Seq Text)
+  { uploadResponseClientIds :: (Seq Text) -- might be null
   , uploadResponseFileInfos :: (Seq FileInfo)
     -- ^ A list of file metadata that has been stored in the database
   } deriving (Read, Show, Eq)
 
 instance A.FromJSON UploadResponse where
   parseJSON = A.withObject "UploadResponse" $ \v -> do
-    uploadResponseClientIds <- v A..: "client_ids"
+    uploadResponseClientIds <- v A..:? "client_ids" A..!= fromList []
     uploadResponseFileInfos <- v A..: "file_infos"
     return UploadResponse { .. }
 
diff --git a/src/Network/Mattermost/Types.hs b/src/Network/Mattermost/Types.hs
--- a/src/Network/Mattermost/Types.hs
+++ b/src/Network/Mattermost/Types.hs
@@ -681,6 +681,7 @@
   = PostProps
   { postPropsOverrideIconUrl  :: Maybe Text
   , postPropsOverrideUsername :: Maybe Text
+  , postPropsFromWebhook      :: Maybe Bool
   , postPropsAttachments      :: Maybe (Seq PostPropAttachment) -- A.Value
   , postPropsNewHeader        :: Maybe Text
   , postPropsOldHeader        :: Maybe Text
@@ -691,6 +692,7 @@
   = PostProps
   { postPropsOverrideIconUrl  = Nothing
   , postPropsOverrideUsername = Nothing
+  , postPropsFromWebhook      = Nothing
   , postPropsAttachments      = Nothing
   , postPropsNewHeader        = Nothing
   , postPropsOldHeader        = Nothing
@@ -700,6 +702,10 @@
   parseJSON = A.withObject "Props" $ \v -> do
     postPropsOverrideIconUrl  <- v .:? "override_icon_url"
     postPropsOverrideUsername <- v .:? "override_username"
+    postPropsFromWebhookStr   <- v .:? "from_webhook"
+    let postPropsFromWebhook = do
+            s <- postPropsFromWebhookStr
+            return $ s == ("true"::Text)
     postPropsAttachments      <- v .:? "attachments"
     postPropsNewHeader        <- v .:? "new_header"
     postPropsOldHeader        <- v .:? "old_header"
@@ -709,6 +715,7 @@
   toJSON PostProps { .. } = A.object $
     [ "override_icon_url" .= v | Just v <- [postPropsOverrideIconUrl ] ] ++
     [ "override_username" .= v | Just v <- [postPropsOverrideUsername] ] ++
+    [ "from_webhook"      .= v | Just v <- [postPropsFromWebhook     ] ] ++
     [ "attachments"       .= v | Just v <- [postPropsAttachments     ] ] ++
     [ "new_header"        .= v | Just v <- [postPropsNewHeader       ] ] ++
     [ "old_header"        .= v | Just v <- [postPropsOldHeader       ] ]