diff --git a/lean/components/docker/lean_runner.py b/lean/components/docker/lean_runner.py
index 67b776a9..4f9b0067 100644
--- a/lean/components/docker/lean_runner.py
+++ b/lean/components/docker/lean_runner.py
@@ -969,7 +969,7 @@ def parse_extra_docker_config(run_options: Dict[str, Any], extra_docker_config:
                     target = run_options["environment"] = {}
                 if isinstance(extra_docker_config["environment"], list):
                     target.update({item[0]: item[1] for item in [
-                        item if not isinstance(item, str) else (item.split("=")[0], item.split("=")[1]) for item in extra_docker_config["environment"]
+                        item if not isinstance(item, str) else item.split("=", 1) for item in extra_docker_config["environment"]
                     ]})
                 elif isinstance(extra_docker_config["environment"], dict):
                     target.update(extra_docker_config["environment"])
diff --git a/tests/components/docker/test_lean_runner.py b/tests/components/docker/test_lean_runner.py
index 6892b443..1ecd0eac 100644
--- a/tests/components/docker/test_lean_runner.py
+++ b/tests/components/docker/test_lean_runner.py
@@ -823,3 +823,11 @@ def path_is_mounted_in_files(path):
 
     assert all([key in backtesting_env and backtesting_env[key] == source_to_target(value)
                 for key, value in paths_to_mount.items()])
+
+
+def test_lean_runner_parses_environment_values_containing_equals_from_extra_docker_configs() -> None:
+    run_options = {}
+    LeanRunner.parse_extra_docker_config(run_options,
+                                         {"environment": ["JAVA_TOOL_OPTIONS=-Dfile.encoding=UTF-8", "TOKEN=abc=="]})
+
+    assert run_options["environment"] == {"JAVA_TOOL_OPTIONS": "-Dfile.encoding=UTF-8", "TOKEN": "abc=="}