diff --git a/action/action-util/src/main/java/com/powsybl/action/util/ProportionalScalable.java b/action/action-util/src/main/java/com/powsybl/action/util/ProportionalScalable.java
index eb0f63a8462..93d4f334373 100644
--- a/action/action-util/src/main/java/com/powsybl/action/util/ProportionalScalable.java
+++ b/action/action-util/src/main/java/com/powsybl/action/util/ProportionalScalable.java
@@ -90,6 +90,12 @@ private static void checkPercentages(List<Float> percentages, List<Scalable> sca
         if (scalables.size() != percentages.size()) {
             throw new IllegalArgumentException("percentage and scalable list must have the same size");
         }
+        if (scalables.isEmpty()) {
+            return;
+        }
+        if (percentages.stream().anyMatch(p -> Float.isNaN(p))) {
+            throw new IllegalArgumentException("There is at least one undefined percentage");
+        }
         double sum = percentages.stream().mapToDouble(Double::valueOf).sum();
         if (Math.abs(100 - sum) > EPSILON) {
             throw new IllegalArgumentException(String.format("Sum of percentages must be equals to 100 (%.2f)", sum));
diff --git a/action/action-util/src/test/java/com/powsybl/action/util/ScalableTest.java b/action/action-util/src/test/java/com/powsybl/action/util/ScalableTest.java
index 6649252d69e..db3fc4e9a46 100644
--- a/action/action-util/src/test/java/com/powsybl/action/util/ScalableTest.java
+++ b/action/action-util/src/test/java/com/powsybl/action/util/ScalableTest.java
@@ -83,7 +83,6 @@ public void testInitialValue() {
         assertEquals(0., Scalable.proportional(Arrays.asList(70.f, 30.f), Arrays.asList(g1, l1)).initialValue(network), 1e-3);
 
         testInvalidProportionalScalable(Collections.singletonList(100.0f), Collections.emptyList());
-        testInvalidProportionalScalable(Collections.emptyList(), Collections.emptyList());
         testInvalidProportionalScalable(Arrays.asList(70.f, 20.f), Arrays.asList(g1, l1));
     }