diff --git a/maven-api-impl/src/main/java/org/apache/maven/internal/impl/model/BuildModelTransformer.java b/maven-api-impl/src/main/java/org/apache/maven/internal/impl/model/BuildModelTransformer.java
index c1ff4d8efab5..abd91f2d92f3 100644
--- a/maven-api-impl/src/main/java/org/apache/maven/internal/impl/model/BuildModelTransformer.java
+++ b/maven-api-impl/src/main/java/org/apache/maven/internal/impl/model/BuildModelTransformer.java
@@ -89,7 +89,15 @@ void handleCiFriendlyVersion(ModelTransformerContext context, Model model, Path
     void handleReactorDependencies(ModelTransformerContext context, Model model, Path pomFile, Model.Builder builder) {
         List<Dependency> newDeps = new ArrayList<>();
         boolean modified = false;
+        String groupId = model.getGroupId();
+        if (groupId == null) {
+            groupId = model.getParent().getGroupId();
+        }
         for (Dependency dep : model.getDependencies()) {
+            if (dep.getGroupId() == null) {
+                dep = dep.withGroupId(groupId);
+                modified = true;
+            }
             if (dep.getVersion() == null) {
                 Model depModel = context.getRawModel(model.getPomFile(), dep.getGroupId(), dep.getArtifactId());
                 if (depModel != null) {