diff --git a/tools/lint/lint.py b/tools/lint/lint.py
index d8fb9fc35ef38d..6645e99e4f9f8a 100644
--- a/tools/lint/lint.py
+++ b/tools/lint/lint.py
@@ -396,6 +396,20 @@ def check_unique_testharness_basenames(repo_root, paths):
     return errors
 
 
+def check_unique_case_insensitive_paths(repo_root, paths):
+    # type: (Text, List[Text]) -> List[rules.Error]
+    seen = {}  # type: Dict[Text, Text]
+    errors = []
+    for path in paths:
+        lower_path = path.lower()
+        if lower_path in seen:
+            context = (seen[lower_path],)
+            errors.append(rules.DuplicatePathCaseInsensitive.error(path, context))
+        else:
+            seen[lower_path] = path
+    return errors
+
+
 def parse_ignorelist(f):
     # type: (IO[Text]) -> Tuple[Ignorelist, Set[Text]]
     """
@@ -1107,7 +1121,8 @@ def process_errors(errors):
 
 path_lints = [check_file_type, check_path_length, check_worker_collision, check_ahem_copy,
               check_mojom_js, check_tentative_directories, check_gitignore_file]
-all_paths_lints = [check_css_globally_unique, check_unique_testharness_basenames]
+all_paths_lints = [check_css_globally_unique, check_unique_testharness_basenames,
+                   check_unique_case_insensitive_paths]
 file_lints = [check_regexp_line, check_parsed, check_python_ast, check_script_metadata,
               check_ahem_system_font]
 
diff --git a/tools/lint/rules.py b/tools/lint/rules.py
index e9bb30b59cff07..125adb07d7f884 100644
--- a/tools/lint/rules.py
+++ b/tools/lint/rules.py
@@ -359,6 +359,14 @@ class DuplicateBasenamePath(Rule):
     to_fix = "rename files so they have unique basename paths"
 
 
+class DuplicatePathCaseInsensitive(Rule):
+    name = "DUPLICATE-CASE-INSENSITIVE-PATH"
+    description = collapse("""
+            Path differs from path %s only in case
+    """)
+    to_fix = "rename files so they are unique irrespective of case"
+
+
 class TentativeDirectoryName(Rule):
     name = "TENTATIVE-DIRECTORY-NAME"
     description = "Directories for tentative tests must be named exactly 'tentative'"
diff --git a/tools/lint/tests/test_path_lints.py b/tools/lint/tests/test_path_lints.py
index 9fefb7a1d7e061..3706a952c61f6a 100644
--- a/tools/lint/tests/test_path_lints.py
+++ b/tools/lint/tests/test_path_lints.py
@@ -3,7 +3,7 @@
 import mock
 import os
 
-from ..lint import check_path
+from ..lint import check_path, check_unique_case_insensitive_paths
 from .base import check_errors
 import pytest
 
@@ -153,3 +153,15 @@ def test_gitignore_negative(path):
     errors = check_path("/foo/", path)
 
     assert errors == []
+
+
+@pytest.mark.parametrize("paths,errors",
+                         [(["a/b.html", "a/B.html"], ["a/B.html"]),
+                          (["A/b.html", "a/b.html"], ["a/b.html"]),
+                          (["a/b.html", "a/c.html"], [])])
+def test_unique_case_insensitive_paths(paths, errors):
+    got_errors = check_unique_case_insensitive_paths(None, paths)
+    assert len(got_errors) == len(errors)
+    for (name, _, path, _), expected_path in zip(got_errors, errors):
+        assert name == "DUPLICATE-CASE-INSENSITIVE-PATH"
+        assert path == expected_path