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 69f70c222f..b879649dfe 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
@@ -28,6 +28,7 @@ import java.util.Optional;
 import org.apache.maven.api.di.Named;
 import org.apache.maven.api.di.Singleton;
 import org.apache.maven.api.model.Dependency;
+import org.apache.maven.api.model.InputLocation;
 import org.apache.maven.api.model.Model;
 import org.apache.maven.api.model.Parent;
 import org.apache.maven.api.services.ModelTransformer;
@@ -83,18 +84,35 @@ public class BuildModelTransformer implements ModelTransformer {
         List<Dependency> newDeps = new ArrayList<>();
         boolean modified = false;
         for (Dependency dep : model.getDependencies()) {
+            Dependency.Builder depBuilder = null;
             if (dep.getVersion() == null) {
                 Model depModel = context.getRawModel(model.getPomFile(), dep.getGroupId(), dep.getArtifactId());
                 if (depModel != null) {
-                    String v = depModel.getVersion();
-                    if (v == null && depModel.getParent() != null) {
-                        v = depModel.getParent().getVersion();
+                    String version = depModel.getVersion();
+                    InputLocation versionLocation = depModel.getLocation("version");
+                    if (version == null && depModel.getParent() != null) {
+                        version = depModel.getParent().getVersion();
+                        versionLocation = depModel.getParent().getLocation("version");
+                    }
+                    depBuilder = Dependency.newBuilder(dep);
+                    depBuilder.version(version).location("version", versionLocation);
+                    if (dep.getGroupId() == null) {
+                        String depGroupId = depModel.getGroupId();
+                        InputLocation groupIdLocation = depModel.getLocation("groupId");
+                        if (depGroupId == null && depModel.getParent() != null) {
+                            depGroupId = depModel.getParent().getGroupId();
+                            groupIdLocation = depModel.getParent().getLocation("groupId");
+                        }
+                        depBuilder.groupId(depGroupId).location("groupId", groupIdLocation);
                     }
-                    dep = dep.withVersion(v);
-                    modified = true;
                 }
             }
-            newDeps.add(dep);
+            if (depBuilder != null) {
+                newDeps.add(depBuilder.build());
+                modified = true;
+            } else {
+                newDeps.add(dep);
+            }
         }
         if (modified) {
             builder.dependencies(newDeps);
diff --git a/maven-api-impl/src/main/java/org/apache/maven/internal/impl/model/DefaultModelTransformerContextBuilder.java b/maven-api-impl/src/main/java/org/apache/maven/internal/impl/model/DefaultModelTransformerContextBuilder.java
index 08a44afcd1..76d94a6d31 100644
--- a/maven-api-impl/src/main/java/org/apache/maven/internal/impl/model/DefaultModelTransformerContextBuilder.java
+++ b/maven-api-impl/src/main/java/org/apache/maven/internal/impl/model/DefaultModelTransformerContextBuilder.java
@@ -83,7 +83,8 @@ class DefaultModelTransformerContextBuilder implements ModelTransformerContextBu
             public Model getRawModel(Path from, String gId, String aId) {
                 Model model = findRawModel(from, gId, aId);
                 if (model != null) {
-                    context.modelByGA.put(new GAKey(gId, aId), new Holder(model));
+                    String groupId = DefaultModelBuilder.getGroupId(model);
+                    context.modelByGA.put(new GAKey(groupId, model.getArtifactId()), new Holder(model));
                     context.modelByPath.put(model.getPomFile(), new Holder(model));
                 }
                 return model;
@@ -214,8 +215,18 @@ class DefaultModelTransformerContextBuilder implements ModelTransformerContextBu
     }
 
     public ModelSource getSource(String groupId, String artifactId) {
-        Set<ModelSource> sources = mappedSources.get(groupId + ":" + artifactId);
-        if (sources == null) {
+        Set<ModelSource> sources;
+        if (groupId != null) {
+            sources = mappedSources.get(groupId + ":" + artifactId);
+            if (sources == null) {
+                return null;
+            }
+        } else if (artifactId != null) {
+            sources = mappedSources.get(artifactId);
+            if (sources == null) {
+                return null;
+            }
+        } else {
             return null;
         }
         return sources.stream()
@@ -231,5 +242,6 @@ class DefaultModelTransformerContextBuilder implements ModelTransformerContextBu
         mappedSources
                 .computeIfAbsent(groupId + ":" + artifactId, k -> new HashSet<>())
                 .add(source);
+        mappedSources.computeIfAbsent(artifactId, k -> new HashSet<>()).add(source);
     }
 }