diff --git a/lexers/embedded/fsharp.xml b/lexers/embedded/fsharp.xml
index f60897977..e1c19ffb4 100644
--- a/lexers/embedded/fsharp.xml
+++ b/lexers/embedded/fsharp.xml
@@ -133,7 +133,7 @@
         <token type="LiteralString"/>
         <push state="string"/>
       </rule>
-      <rule pattern="\b(open|module)(\s+)([\w.]+)">
+      <rule pattern="\b(open type|open|module)(\s+)([\w.]+)">
         <bygroups>
           <token type="Keyword"/>
           <token type="Text"/>
diff --git a/lexers/testdata/fsharp/fsharp_open_static_class.actual b/lexers/testdata/fsharp/fsharp_open_static_class.actual
new file mode 100644
index 000000000..00bc4b742
--- /dev/null
+++ b/lexers/testdata/fsharp/fsharp_open_static_class.actual
@@ -0,0 +1,4 @@
+open type System.Math
+
+module A =
+    open type System.Math
diff --git a/lexers/testdata/fsharp/fsharp_open_static_class.expected b/lexers/testdata/fsharp/fsharp_open_static_class.expected
new file mode 100644
index 000000000..1c58e26b0
--- /dev/null
+++ b/lexers/testdata/fsharp/fsharp_open_static_class.expected
@@ -0,0 +1,16 @@
+[
+  {"type":"Keyword","value":"open type"},
+  {"type":"Text","value":" "},
+  {"type":"NameNamespace","value":"System.Math"},
+  {"type":"Text","value":"\n\n"},
+  {"type":"Keyword","value":"module"},
+  {"type":"Text","value":" "},
+  {"type":"NameNamespace","value":"A"},
+  {"type":"Text","value":" "},
+  {"type":"Operator","value":"="},
+  {"type":"Text","value":"\n    "},
+  {"type":"Keyword","value":"open type"},
+  {"type":"Text","value":" "},
+  {"type":"NameNamespace","value":"System.Math"},
+  {"type":"Text","value":"\n"}
+]