diff --git a/create_algorithm_package.sh b/create_algorithm_package.sh
index 68ea5e6ceb6b75bd79da4e7fd96c3a8fb5ad74f2..b7ad096a7fb46c8cf22915852433e73e8bff9c61 100755
--- a/create_algorithm_package.sh
+++ b/create_algorithm_package.sh
@@ -66,7 +66,7 @@ if [[ ${use_iri_prefix} == true ]]
 then
   project_name="iri_${input_name}"
 else
-  if [[ ! -z "$input_prefix"  ]]
+  if [[ "$input_prefix" != ":"  ]]
   then
     project_name="${input_prefix}_${input_name}"
   else
diff --git a/create_driver_package.sh b/create_driver_package.sh
index 27cd1bc583644b65e20b71cac8bc7b9a9ddddb9f..72a6d87c5de34568c4ecca87a541bab3920fc992 100755
--- a/create_driver_package.sh
+++ b/create_driver_package.sh
@@ -63,7 +63,7 @@ if [[ ${use_iri_prefix} == true ]]
 then
   project_name="iri_${input_name}"
 else
-  if [[ ! -z "$input_prefix"  ]]
+  if [[ "$input_prefix" != ":" ]]
   then
     project_name="${input_prefix}_${input_name}"
   else