diff --git a/man/systemd.exec.xml b/man/systemd.exec.xml
index 45a4422dc..8fd75d274 100644
--- a/man/systemd.exec.xml
+++ b/man/systemd.exec.xml
@@ -263,7 +263,8 @@
         <listitem><para>Similar to <varname>Environment=</varname> but
         reads the environment variables from a text file. The text
         file should contain new-line-separated variable assignments.
-        Empty lines and lines starting with ; or # will be ignored,
+        Empty lines, lines without an <literal>=</literal> separator,
+        or lines starting with ; or # will be ignored,
         which may be used for commenting. A line ending with a
         backslash will be concatenated with the following one,
         allowing multiline variable definitions. The parser strips