diff --git a/src/spdx_tools/spdx/validation/uri_validators.py b/src/spdx_tools/spdx/validation/uri_validators.py
index c14d196f4..1763ebd25 100644
--- a/src/spdx_tools/spdx/validation/uri_validators.py
+++ b/src/spdx_tools/spdx/validation/uri_validators.py
@@ -9,7 +9,7 @@
 
 url_pattern = (
     "(http:\\/\\/www\\.|https:\\/\\/www\\.|http:\\/\\/|https:\\/\\/|ssh:\\/\\/|git:\\/\\/|svn:\\/\\/|sftp:"
-    "\\/\\/|ftp:\\/\\/)?([\\w\\-.!~*'()%;:&=+$,]+@)?[a-z0-9]+([\\-\\.]{1}[a-z0-9]+){0,100}\\.[a-z]{2,5}"
+    "\\/\\/|ftp:\\/\\/)?([\\w\\-.!~*'()%;:&=+$,]+@)?[a-zA-Z0-9]+([\\-\\.]{1}[a-zA-Z0-9]+){0,100}\\.[a-zA-Z]{2,5}"
     "(:[0-9]{1,5})?(\\/.*)?"
 )
 supported_download_repos: str = "(git|hg|svn|bzr)"