diff --git a/Containerfile.5.md b/Containerfile.5.md
index 12245e5..48374c7 100644
--- a/Containerfile.5.md
+++ b/Containerfile.5.md
@@ -54,11 +54,11 @@ A Containerfile is similar to a Makefile.
 
 # FORMAT
 
-  `FROM image`
+  `FROM image [AS <name>]`
 
-  `FROM image:tag`
+  `FROM image:tag [AS <name>]`
 
-  `FROM image@digest`
+  `FROM image@digest [AS <name>]`
 
   -- The **FROM** instruction sets the base image for subsequent instructions. A
   valid Containerfile must have either **ARG** or *FROM** as its first instruction.
@@ -82,6 +82,9 @@ A Containerfile is similar to a Makefile.
   -- If no digest is given to the **FROM** instruction, container engines apply the
   `latest` tag. If the used tag does not exist, an error is returned.
 
+  -- A name can be assigned to a build stage by adding **AS name** to the instruction. 
+  The name can be referenced later in the Containerfile using the **FROM** or **COPY --from=<name>** instructions.
+
 **MAINTAINER**
   -- **MAINTAINER** sets the Author field for the generated images.
   Useful for providing users with an email or url for support.
@@ -362,10 +365,10 @@ The secret needs to be passed to the build using the --secret flag. The final im
   -- **COPY** has two forms:
 
   ```
-  COPY <src> <dest>
+  COPY [--chown=<user>:<group>] [--chmod=<mode>] <src> <dest>
 
   # Required for paths with whitespace
-  COPY ["<src>",... "<dest>"]
+  COPY [--chown=<user>:<group>] [--chmod=<mode>] ["<src>",... "<dest>"]
   ```
 
   The **COPY** instruction copies new files from `<src>` and
@@ -378,6 +381,16 @@ The secret needs to be passed to the build using the --secret flag. The final im
   attempt to unpack it.  All new files and directories are created with mode **0755**
   and with the uid and gid of **0**.
 
+  `--chown=<user>:<group>` changes the ownership of new files and directories.
+  Supports names, if defined in the containers `/etc/passwd` and `/etc/groups` files, or using
+  uid and gid integers. The build will fail if a user or group name can't be mapped in the container.
+  Numeric id's are set without looking them up in the container.
+
+  `--chmod=<mode>` changes the mode of new files and directories.
+
+  The optional flag `--from=name` can be used to copy files from a named previous build stage. It
+  changes the context of `<src>` from the build context to the named build stage.
+
 **ENTRYPOINT**
   -- **ENTRYPOINT** has two forms: