diff --git a/python/obitools3/commands/grep.pyx b/python/obitools3/commands/grep.pyx
index 733a530..63ac52b 100644
--- a/python/obitools3/commands/grep.pyx
+++ b/python/obitools3/commands/grep.pyx
@@ -46,7 +46,7 @@ def run(config):
     uri = config['obi']['outputURI'].split('/')
     if len(uri)==2:
         # Check that input and output DMS are the same (predicate, to discuss)
-        if config['obi']['inputURI'].split(b'/')[0] != uri[0]:
+        if config['obi']['inputURI'].split('/')[0] != uri[0]:
             raise Exception("Input and output DMS must be the same")
         output_view_name = uri[1]
     else: