diff --git a/builtins/2.7/__builtin__.pyi b/builtins/2.7/__builtin__.pyi
index 7c5280c2e..e34aa90d6 100644
--- a/builtins/2.7/__builtin__.pyi
+++ b/builtins/2.7/__builtin__.pyi
@@ -725,6 +725,11 @@ def __import__(name: unicode,
 def globals() -> Dict[str, Any]: ...
 def locals() -> Dict[str, Any]: ...
 
+# Actually the type of Ellipsis is <type 'ellipsis'>, but since it's
+# not exposed anywhere under that name, we make it private here.
+class _ellipsis: ...
+Ellipsis = ...  # type: _ellipsis
+
 # TODO: buffer support is incomplete; e.g. some_string.startswith(some_buffer) doesn't type check.
 AnyBuffer = TypeVar('AnyBuffer', str, unicode, bytearray, buffer)
 
@@ -749,6 +754,7 @@ class Exception(BaseException): ...
 class StopIteration(Exception): ...
 class StandardError(Exception): ...
 class ArithmeticError(StandardError): ...
+class BufferError(StandardError): ...
 class EnvironmentError(StandardError):
     errno = 0
     strerror = ''
diff --git a/builtins/3/builtins.pyi b/builtins/3/builtins.pyi
index 838d7209b..58043f712 100644
--- a/builtins/3/builtins.pyi
+++ b/builtins/3/builtins.pyi
@@ -712,11 +712,10 @@ def __import__(name: str, globals: Dict[str, Any] = {}, locals: Dict[str, Any] =
 
 # Ellipsis
 
-class ellipsis:
-    # TODO not defined in builtins!
-    def __init__(self) -> None: ...
-
-Ellipsis = ellipsis()
+# Actually the type of Ellipsis is <type 'ellipsis'>, but since it's
+# not exposed anywhere under that name, we make it private here.
+class _ellipsis: ...
+Ellipsis = ...  # type: _ellipsis
 
 # Exceptions