diff --git a/test/test_007_dataset_validation.py b/test/test_007_dataset_validation.py
new file mode 100644
index 0000000..493adf2
--- /dev/null
+++ b/test/test_007_dataset_validation.py
@@ -0,0 +1,42 @@
+import unittest
+from pathlib import Path
+from scripts.validate_cleaned_dataset import validate
+ 
+class TestDatasetValidationTicket(unittest.TestCase):
+    def test_invalid_food_data(self):
+        # Various invalid cases: missing fields, wrong types, negative values, invalid categories
+        invalid_products = [
+            {},  # completely empty
+            {"barcode": None, "productName": None},
+            {"barcode": "abc", "productName": 123},
+            {"barcode": "123", "productName": "Test", "completeness": -0.5},
+            {"barcode": "123", "productName": "Test", "categories": [123]},
+            {"barcode": "123", "productName": "Test", "standardCategory": "not_a_real_category"},
+            {"barcode": "123", "productName": "Test", "nutriscoreGrade": "z"},
+            {"barcode": "123", "productName": "Test", "nutriments": {"fat_100g": -1}},
+        ]
+        try:
+            report = validate(invalid_products, Path("invalid.json"))
+        except Exception as e:
+            self.fail(f"Validation crashed on invalid data: {e}")
+        self.assertFalse(report["ok"])
+        total_issues = sum(check["issue_count"] for check in report["checks"].values())
+        self.assertGreater(total_issues, 0)
+ 
+    def test_incomplete_food_data(self):
+        # Incomplete: only required fields, missing recommended
+        incomplete_products = [
+            {"barcode": "1234567890123", "productName": "Test"},
+            {"barcode": "2345678901234", "productName": "Test2", "brand": ""},
+        ]
+        try:
+            report = validate(incomplete_products, Path("incomplete.json"))
+        except Exception as e:
+            self.fail(f"Validation crashed on incomplete data: {e}")
+        self.assertIn("ok", report)
+        missing = report["checks"]["missing_product_fields"]
+        self.assertGreaterEqual(missing["field_counts"].get("brand", 0), 1)
+ 
+if __name__ == "__main__":
+    unittest.main()
+ 
\ No newline at end of file