diff --git a/docs/src/fileformat.md b/docs/src/fileformat.md
index d70b727f..ce28a3ef 100644
--- a/docs/src/fileformat.md
+++ b/docs/src/fileformat.md
@@ -58,6 +58,10 @@ certain lines:
 Lines *starting* with one of these tokens are filtered out in the
 [preprocessing step](@ref Pre-processing).
 
+!!! tip
+    The tokens can also be negated, for example a line starting with `#!nb` would
+    be included in markdown and script output, but filtered out for notebook output.
+
 Suppose, for example, that we want to include a docstring within a `@docs` block
 using Documenter. Obviously we don't want to include this in the notebook,
 since `@docs` is Documenter syntax that the notebook will not understand. This
diff --git a/src/Literate.jl b/src/Literate.jl
index c7db5199..3f1d0aa2 100644
--- a/src/Literate.jl
+++ b/src/Literate.jl
@@ -142,18 +142,27 @@ function replace_default(content, sym;
     push!(repls, r".*#src$\n?"m => "")
 
     if sym === :md
-        push!(repls, r"^#nb.*\n?"m => "") # remove #nb lines
-        push!(repls, r"^#jl.*\n?"m => "") # remove leading #jl lines
-        push!(repls, r"^#md "m => "")     # remove leading #md
+        push!(repls, r"^#md "m => "")      # remove leading #md
+        push!(repls, r"^#!md.*\n?"m => "") # remove leading #!md lines
+        push!(repls, r"^#nb.*\n?"m => "")  # remove #nb lines
+        push!(repls, r"^#!nb "m => "")     # remove leading #!nb
+        push!(repls, r"^#jl.*\n?"m => "")  # remove leading #jl lines
+        push!(repls, r"^#!jl "m => "")     # remove leading #!jl
     elseif sym === :nb
-        push!(repls, r"^#md.*\n?"m => "") # remove #md lines
-        push!(repls, r"^#jl.*\n?"m => "") # remove leading #jl lines
-        push!(repls, r"^#nb "m => "")     # remove leading #nb
+        push!(repls, r"^#md.*\n?"m => "")  # remove #md lines
+        push!(repls, r"^#!md "m => "")     # remove leading #!md
+        push!(repls, r"^#nb "m => "")      # remove leading #nb
+        push!(repls, r"^#!nb.*\n?"m => "") # remove #!nb lines
+        push!(repls, r"^#jl.*\n?"m => "")  # remove leading #jl lines
+        push!(repls, r"^#!jl "m => "")     # remove leading #!jl
         push!(repls, r"```math(.*?)```"s => s"\\begin{equation}\1\\end{equation}")
     else # sym === :jl
-        push!(repls, r"^#md.*\n?"m => "") # remove #md lines
-        push!(repls, r"^#nb.*\n?"m => "") # remove #nb lines
-        push!(repls, r"^#jl "m => "")     # remove leading #jl
+        push!(repls, r"^#md.*\n?"m => "")  # remove #md lines
+        push!(repls, r"^#!md "m => "")     # remove leading #!md
+        push!(repls, r"^#nb.*\n?"m => "")  # remove #nb lines
+        push!(repls, r"^#!nb "m => "")     # remove leading #!nb
+        push!(repls, r"^#jl "m => "")      # remove leading #jl
+        push!(repls, r"^#!jl.*\n?"m => "") # remove #!jl lines
     end
 
     # name
diff --git a/test/runtests.jl b/test/runtests.jl
index 044f4e32..8aff4926 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -165,10 +165,16 @@ content = """
     x = 1
     #md # Only markdown
     #md x + 1
+    #!md # Not markdown
+    #!md x * 1
     #nb # Only notebook
     #nb x + 2
+    #!nb # Not notebook
+    #!nb x * 2
     #jl # Only script
     #jl x + 3
+    #!jl # Not script
+    #!jl x * 3
     #src # Source code only
     Source code only          #src
     ## # Comment
@@ -221,6 +227,10 @@ content = """
             expected_script = """
             x = 1
 
+            x * 1
+
+            x * 2
+
             x + 3
             # # Comment
             # another comment
@@ -319,6 +329,18 @@ end
 
             ```@example inputfile
             x + 1
+            ```
+
+            Not notebook
+
+            ```@example inputfile
+            x * 2
+            ```
+
+            Not script
+
+            ```@example inputfile
+            x * 3
             # # Comment
             # another comment
             ```
@@ -461,6 +483,18 @@ end
                ]
             """,
 
+            """
+               "source": [
+                "Not markdown"
+               ],
+            """,
+
+            """
+               "source": [
+                "x * 1"
+               ],
+            """,
+
             """
                "source": [
                 "Only notebook"
@@ -469,10 +503,22 @@ end
 
             """
                "source": [
-                "x + 2\\n",
+                "x + 2"
+               ]
+            """,
+
+            """
+               "source": [
+                "Not script"
+               ],
+            """,
+
+            """
+               "source": [
+                "x * 3\\n",
                 "# # Comment\\n",
                 "# another comment"
-               ]
+               ],
             """,
 
             """