diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8004d9c01..c8085c362 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,7 +9,6 @@ Find out more about isort's release policy [here](https://pycqa.github.io/isort/
   - Made all exceptions pickleable.
   - Fixed #1779: Pylama integration ignores pylama specific isort config overrides.
   - Fixed #1781: `--from-first` CLI flag shouldn't take any arguments.
-  - Fixed #1785: `_ast` module incorrectly excluded from stdlib definition.
 
 ### 5.9.2 July 8th 2021
   - Improved behavior of `isort --check --atomic` against Cython files.
diff --git a/isort/stdlibs/py27.py b/isort/stdlibs/py27.py
index a9bc99d0c..87aa67f1f 100644
--- a/isort/stdlibs/py27.py
+++ b/isort/stdlibs/py27.py
@@ -40,7 +40,6 @@
     "UserString",
     "W",
     "__builtin__",
-    "_ast",
     "_winreg",
     "abc",
     "aepack",
diff --git a/isort/stdlibs/py35.py b/isort/stdlibs/py35.py
index 29ab9aeba..274d8a7d1 100644
--- a/isort/stdlibs/py35.py
+++ b/isort/stdlibs/py35.py
@@ -6,7 +6,6 @@
 """
 
 stdlib = {
-    "_ast",
     "_dummy_thread",
     "_thread",
     "abc",
diff --git a/isort/stdlibs/py36.py b/isort/stdlibs/py36.py
index 59ebd24cb..8ae02a150 100644
--- a/isort/stdlibs/py36.py
+++ b/isort/stdlibs/py36.py
@@ -6,7 +6,6 @@
 """
 
 stdlib = {
-    "_ast",
     "_dummy_thread",
     "_thread",
     "abc",
diff --git a/isort/stdlibs/py37.py b/isort/stdlibs/py37.py
index e0ad1228a..0eb1dd6fa 100644
--- a/isort/stdlibs/py37.py
+++ b/isort/stdlibs/py37.py
@@ -6,7 +6,6 @@
 """
 
 stdlib = {
-    "_ast",
     "_dummy_thread",
     "_thread",
     "abc",
diff --git a/isort/stdlibs/py38.py b/isort/stdlibs/py38.py
index 3d89fd26b..9bcea9a16 100644
--- a/isort/stdlibs/py38.py
+++ b/isort/stdlibs/py38.py
@@ -6,7 +6,6 @@
 """
 
 stdlib = {
-    "_ast",
     "_dummy_thread",
     "_thread",
     "abc",
diff --git a/isort/stdlibs/py39.py b/isort/stdlibs/py39.py
index 4b7dd5954..7bcb8f2b7 100644
--- a/isort/stdlibs/py39.py
+++ b/isort/stdlibs/py39.py
@@ -6,7 +6,6 @@
 """
 
 stdlib = {
-    "_ast",
     "_thread",
     "abc",
     "aifc",
diff --git a/scripts/mkstdlibs.py b/scripts/mkstdlibs.py
index cf5237987..ee08ba1d0 100755
--- a/scripts/mkstdlibs.py
+++ b/scripts/mkstdlibs.py
@@ -31,7 +31,7 @@ class FakeApp:
     invdata = fetch_inventory(FakeApp(), "", url)
 
     # Any modules we want to enforce across Python versions stdlib can be included in set init
-    modules = {"_ast", "posixpath", "ntpath", "sre_constants", "sre_parse", "sre_compile", "sre"}
+    modules = {"posixpath", "ntpath", "sre_constants", "sre_parse", "sre_compile", "sre"}
     for module in invdata["py:module"]:
         root, *_ = module.split(".")
         if root not in ["__future__", "__main__"]: