diff --git a/meta_creator/metadata_extractor.py b/meta_creator/metadata_extractor.py
index 0f02de7..81874c4 100644
--- a/meta_creator/metadata_extractor.py
+++ b/meta_creator/metadata_extractor.py
@@ -12,10 +12,8 @@
 from .gitlab_metadata import get_gitlab_metadata
 from .read_tokens import read_token_from_file
 from .hermes_process import run_hermes_commands
-import json
-import os
-
-
+from .spdx_utils import validate_license 
+             
 #################### getting metadata from github/gitlab project ####################
 
 @csrf_exempt
@@ -55,7 +53,15 @@ def data_extraction(request):
             if not extracted_metadata:
                 extracted_metadata = get_gitlab_metadata(gl_url, default_access_token_gitlab)
 
-            result['metadata'] = init_curated_metadata(extracted_metadata)
+            output = validate_license(extracted_metadata)
+            if output.get('success') is False:
+                return {
+                    'success': False,
+                    'errors': 'No valid license found in metadata.'
+                }
+            else:
+                result['metadata'] = init_curated_metadata(extracted_metadata)
+            
 
         else: 
             # TODO we need to pass the token to hermes_process
@@ -66,12 +72,20 @@ def data_extraction(request):
             #     hermes_metadata = get_github_metadata(gl_url, default_access_token_GH)
 
             if isinstance(hermes_metadata, dict):
-                result['metadata'] = init_curated_metadata(hermes_metadata.get('metadata'))
-                result['warnings'].extend(hermes_metadata.get('warnings', []))
-                result['errors'].extend(hermes_metadata.get('errors', []))
-                result['success'] = hermes_metadata.get('success', False)
+                extracted_metadata = hermes_metadata.get('metadata')
+                if extracted_metadata:
+                    output = validate_license(extracted_metadata)
+                    if output.get('success') is False:
+                        return {
+                            'success': False,
+                            'errors': 'No valid license found in metadata.'
+                        }
+                    else:
+                        result['metadata'] = init_curated_metadata(hermes_metadata.get('metadata'))
+                        result['warnings'].extend(hermes_metadata.get('warnings', []))
+                        result['errors'].extend(hermes_metadata.get('errors', []))
+                        result['success'] = hermes_metadata.get('success', False)
             else:
                 result['success'] = False
                 result['errors'].append("HERMES returned unexpected result format.")
-        
         return result
\ No newline at end of file
diff --git a/meta_creator/spdx_utils.py b/meta_creator/spdx_utils.py
new file mode 100644
index 0000000..e1ff531
--- /dev/null
+++ b/meta_creator/spdx_utils.py
@@ -0,0 +1,58 @@
+import requests
+import re
+from functools import lru_cache
+
+SPDX_URL = 'https://raw.githubusercontent.com/spdx/license-list-data/master/json/licenses.json'
+
+@lru_cache(maxsize=1)
+def get_spdx_licenses():
+    licenses = set()
+    response = requests.get(SPDX_URL, timeout=10)
+    response.raise_for_status()
+    data = response.json()
+
+    for license_entry in data.get("licenses", []):
+        if not license_entry.get("isDeprecatedLicenseId", False):
+            licenses.add(license_entry["licenseId"])
+
+    return licenses
+
+def extract_license_from_metadata(metadata):
+    if not isinstance(metadata, dict):
+        return None
+
+    def extract_spdx_id_from_url(url):
+        match = re.search(r'spdx\.org/licenses/([A-Za-z0-9\.-]+)', url)
+        return match.group(1) if match else None
+
+    license_data = metadata.get('license')
+
+    if isinstance(license_data, list):
+        for item in license_data:
+            if isinstance(item, str):
+                spdx_id = extract_spdx_id_from_url(item)
+                if spdx_id:
+                    return spdx_id
+
+    if isinstance(license_data, dict):
+        return license_data.get('spdx_id') or license_data.get('key')
+
+    if isinstance(license_data, str):
+        return extract_spdx_id_from_url(license_data) or license_data.strip()
+
+    if 'spdx_license' in metadata:
+        return metadata['spdx_license'].strip()
+
+    return None
+
+def validate_license(metadata):
+    license_id = extract_license_from_metadata(metadata)
+
+    if not license_id:
+        return {'success': False}
+
+    spdx_licenses = get_spdx_licenses()
+    if license_id in spdx_licenses:
+        return {'success': True}
+    else:
+        return {'success': False}
\ No newline at end of file