diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 8159e420..deaa24c8 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -11,4 +11,9 @@ repos:
         entry: python tests/test_duplicate_designations.py
         language: python
         files: lineages.csv
+    -   id: duplicate-lineage-in-notes
+        name: Test lineage_notes.txt for duplicate first column entries
+        entry: python tests/test_duplicate_lineage_in_notes.py
+        language: python
+        files: lineage_notes.txt
 
diff --git a/tests/test_duplicate_lineage_in_notes.py b/tests/test_duplicate_lineage_in_notes.py
new file mode 100755
index 00000000..24279f00
--- /dev/null
+++ b/tests/test_duplicate_lineage_in_notes.py
@@ -0,0 +1,42 @@
+#!/usr/bin/env python3
+
+
+def check_for_duplicates(filename, buffer_size=1024 * 1024):  # 1MB buffer
+    seen = set()
+    buffer = ""
+    is_valid = True
+    line_counter = 0  # Counter for tracking the number of lines seen
+
+    with open(filename, "r") as f:
+        while True:
+            chunk = f.read(buffer_size)
+            if not chunk:
+                break
+
+            buffer += chunk
+            lines = buffer.split("\n")
+            for i in range(len(lines) - 1):
+                line_counter += 1  # Increment the line counter
+                fields = lines[i].split("\t")
+
+                if len(fields) > 2:
+                    print(f"lineage_notes.txt: Line {line_counter} has more than 2 fields `{fields}`")
+                    is_valid = False
+
+                field = fields[0]
+                if field in seen:
+                    print(f"Duplicate {field} found in line {line_counter}")
+                    is_valid = False
+                seen.add(field)
+            buffer = lines[
+                -1
+            ]  # keep the last, potentially incomplete line for the next iteration
+
+    return is_valid
+
+
+# Usage
+if check_for_duplicates("lineage_notes.txt") is False:
+    exit(1)  # Exit with status 1 if duplicates found
+else:
+    exit(0)  # Exit with status 0 otherwise