diff --git a/java-client/src/test/java/org/opensearch/client/opensearch/_types/aggregations/FilterAggregateTest.java b/java-client/src/test/java/org/opensearch/client/opensearch/_types/aggregations/FilterAggregateTest.java
new file mode 100644
index 0000000000..9974dc0032
--- /dev/null
+++ b/java-client/src/test/java/org/opensearch/client/opensearch/_types/aggregations/FilterAggregateTest.java
@@ -0,0 +1,13 @@
+package org.opensearch.client.opensearch._types.aggregations;
+
+import org.junit.Test;
+import org.opensearch.client.opensearch.model.ModelTestCase;
+
+public class FilterAggregateTest extends ModelTestCase {
+    @Test
+    public void serializesNestedAggregates() {
+        String json = "{\"sum#l2_result\":{\"value\":1.0},\"doc_count\":1}";
+        FilterAggregate aggregate = fromJson(json, FilterAggregate._DESERIALIZER);
+        assertEquals(json, toJson(aggregate));
+    }
+}