diff --git a/executable_semantics/syntax/BUILD b/executable_semantics/syntax/BUILD
index 4fd6560ed823..1bc80df2c5c6 100644
--- a/executable_semantics/syntax/BUILD
+++ b/executable_semantics/syntax/BUILD
@@ -2,9 +2,6 @@
 # Exceptions. See /LICENSE for license information.
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
-# TODO(https://github.com/carbon-language/carbon-lang/issues/266):
-# Migrate bison/flex usage to a more hermetic bazel build.
-
 load("@rules_cc//cc:defs.bzl", "cc_binary", "cc_library")
 
 package(default_visibility = ["//executable_semantics:__subpackages__"])