diff --git a/distroless/private/flatten.sh b/distroless/private/flatten.sh
index 3fdcbd9..25b6762 100755
--- a/distroless/private/flatten.sh
+++ b/distroless/private/flatten.sh
@@ -35,16 +35,25 @@ if [[ "$deduplicate" == "True" ]]; then
     # number of occurrences of each path, and the second pass determines whether each entry is the final (or only)
     # occurrence of that path.
 
-    $bsdtar --confirmation "$@" 2< <("${awk}" '{
-        count[$1]++;
+    $bsdtar --confirmation "$@" 2< <("${awk}" '
+    function normalize(p) {
+        # Strip leading "./" and trailing "/" so that "./etc/" and "etc/" are treated as the same path.
+        sub(/^\.\//, "", p)
+        sub(/\/$/, "", p)
+        return p
+    }
+    {
+        key = normalize($1)
+        count[key]++
         files[NR] = $1
+        keys[NR] = key
     }
     END {
         ORS=""
         for (i=1; i<=NR; i++) {
-            seen[files[i]]++
+            seen[keys[i]]++
             keep="n"
-            if (count[files[i]] == seen[files[i]]) {
+            if (count[keys[i]] == seen[keys[i]]) {
                 keep="y"
             }
             for (j=0; j<31; j++) print keep
diff --git a/examples/flatten/BUILD.bazel b/examples/flatten/BUILD.bazel
index 67d7dd5..a4dbfca 100644
--- a/examples/flatten/BUILD.bazel
+++ b/examples/flatten/BUILD.bazel
@@ -120,3 +120,42 @@ examples/flatten/dir/sub/
 examples/flatten/dir/sub/content.txt
 """,
 )
+
+# Flatten with deduplication across mixed path formats ("./etc/" vs "etc/").
+# Tars produced by different tools use inconsistent path prefixes; deduplication
+# must normalize them so the merged layer contains each path only once.
+tar(
+    name = "dotslash_tar",
+    compress = "gzip",
+    mtree = [
+        "./etc/ type=dir uid=0 gid=0 mode=0755 time=0.0",
+        "./etc/sub/ type=dir uid=0 gid=0 mode=0755 time=0.0",
+    ],
+)
+
+tar(
+    name = "nodotslash_tar",
+    compress = "gzip",
+    mtree = [
+        "etc/ type=dir uid=0 gid=0 mode=0755 time=0.0",
+        "etc/sub/ type=dir uid=0 gid=0 mode=0755 time=0.0",
+    ],
+)
+
+flatten(
+    name = "flatten_dedup_normalize",
+    deduplicate = True,
+    tars = [
+        ":dotslash_tar",
+        ":nodotslash_tar",
+    ],
+)
+
+assert_tar_listing(
+    name = "test_flatten_dedup_normalize",
+    actual = "flatten_dedup_normalize",
+    expected = """\
+etc/
+etc/sub/
+""",
+)