diff --git a/PyInstaller/building/datastruct.py b/PyInstaller/building/datastruct.py
index c5b961d3d6..078b592101 100644
--- a/PyInstaller/building/datastruct.py
+++ b/PyInstaller/building/datastruct.py
@@ -337,8 +337,10 @@ def normalize_pyz_toc(toc):
 
 def _normalize_toc(toc, toc_type_priorities, type_case_normalization_fcn=lambda typecode: False):
     tmp_toc = dict()
-    for entry in toc:
-        dest_name, src_name, typecode = entry
+    for dest_name, src_name, typecode in toc:
+        # Always sanitize the dest_name with `os.path.normpath` to remove any local loops with parent directory path
+        # components. `pathlib` does not seem to offer equivalent functionality.
+        dest_name = os.path.normpath(dest_name)
 
         # Normalize the destination name for uniqueness. Use `pathlib.PurePath` to ensure that keys are both
         # case-normalized (on OSes where applicable) and directory-separator normalized (just in case).
@@ -350,12 +352,12 @@ def _normalize_toc(toc, toc_type_priorities, type_case_normalization_fcn=lambda
         existing_entry = tmp_toc.get(entry_key)
         if existing_entry is None:
             # Entry does not exist - insert
-            tmp_toc[entry_key] = entry
+            tmp_toc[entry_key] = (dest_name, src_name, typecode)
         else:
             # Entry already exists - replace if its typecode has higher priority
             _, _, existing_typecode = existing_entry
             if toc_type_priorities.get(typecode, 0) > toc_type_priorities.get(existing_typecode, 0):
-                tmp_toc[entry_key] = entry
+                tmp_toc[entry_key] = (dest_name, src_name, typecode)
 
     # Return the items as list. The order matches the original order due to python dict maintaining the insertion order.
     return list(tmp_toc.values())
diff --git a/tests/unit/test_toc_normalization.py b/tests/unit/test_toc_normalization.py
index 0a090bfb87..4e861a6263 100644
--- a/tests/unit/test_toc_normalization.py
+++ b/tests/unit/test_toc_normalization.py
@@ -11,6 +11,7 @@
 
 # Tests for explicit TOC list normalization that replaced the implicit normalization with class:``TOC``.
 import copy
+import pathlib
 
 from PyInstaller import compat
 from PyInstaller.building.datastruct import normalize_pyz_toc, normalize_toc
@@ -21,7 +22,7 @@
     ('libpython3.10.so', '/usr/lib64/libpython3.10.so', 'BINARY'),
     ('libsomething.so', '/usr/local/lib64/libsomething.so', 'BINARY'),
     ('README', '/home/user/tmp/README', 'DATA'),
-    ('data/data.csv', '/home/user/tmp/data/data.csv', 'DATA'),
+    (str(pathlib.PurePath('data/data.csv')), '/home/user/tmp/data/data.csv', 'DATA'),
     ('dependency.bin', 'other_multipackage:dependency.bin', 'DEPENDENCY'),
     ('myextension.so', 'myextension.so', 'EXTENSION'),
 ]
@@ -125,6 +126,34 @@ def test_normalize_toc_multipackage_dependency():
     assert sorted(normalized_toc) == sorted(expected_toc)
 
 
+def test_normalize_toc_with_parent_pardir_loops():
+    # Check that de-duplication works even if destination paths contain local loop with parent directory (..) components
+    # but can be normalized to the same path. Furthermore, we expect TOC normalization to sanitize the dest_name with
+    # normalized version.
+    toc = [
+        (
+            str(pathlib.PurePath('numpy/core/../../numpy.libs/libquadmath-2d0c479f.so.0.0.0')),
+            '/path/to/venv/lib/python3.11/site-packages/numpy/core/../../numpy.libs/libquadmath-2d0c479f.so.0.0.0',
+            'BINARY',
+        ),
+        (
+            str(pathlib.PurePath('numpy/linalg/../../numpy.libs/libquadmath-2d0c479f.so.0.0.0')),
+            '/path/to/venv/lib/python3.11/site-packages/numpy/linalg/../../numpy.libs/libquadmath-2d0c479f.so.0.0.0',
+            'BINARY',
+        ),
+    ]
+    expected_toc = [
+        (
+            str(pathlib.PurePath('numpy.libs/libquadmath-2d0c479f.so.0.0.0')),
+            '/path/to/venv/lib/python3.11/site-packages/numpy/core/../../numpy.libs/libquadmath-2d0c479f.so.0.0.0',
+            'BINARY',
+        ),
+    ]
+
+    normalized_toc = normalize_toc(toc)
+    assert sorted(normalized_toc) == sorted(expected_toc)
+
+
 # Tests for PYZ TOC normalization.
 _BASE_PYZ_TOC = [
     ('copy', '/usr/lib64/python3.11/copy.py', 'PYMODULE'),