diff --git a/pom.xml b/pom.xml
index 880c401..514062a 100644
--- a/pom.xml
+++ b/pom.xml
@@ -86,6 +86,26 @@
             <version>3.27.7</version>
             <scope>test</scope>
         </dependency>
+
+        <!-- Lombok for code generation (used by ArtifactV2) -->
+        <dependency>
+            <groupId>org.projectlombok</groupId>
+            <artifactId>lombok</artifactId>
+            <version>1.18.36</version>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.google.code.findbugs</groupId>
+            <artifactId>findbugs-annotations</artifactId>
+            <version>3.0.1</version>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.checkerframework</groupId>
+            <artifactId>checker-qual</artifactId>
+            <version>3.48.4</version>
+            <scope>provided</scope>
+        </dependency>
     </dependencies>
 
     <build>
@@ -309,4 +329,4 @@
             -->
         </plugins>
     </build>
-</project>
\ No newline at end of file
+</project>
diff --git a/src/test/java/com/solubris/enforcer/UnusedPropertyRuleTest.java b/src/test/java/com/solubris/enforcer/UnusedPropertyRuleTest.java
new file mode 100644
index 0000000..3c53675
--- /dev/null
+++ b/src/test/java/com/solubris/enforcer/UnusedPropertyRuleTest.java
@@ -0,0 +1,287 @@
+package com.solubris.enforcer;
+
+import org.apache.maven.enforcer.rule.api.EnforcerLogger;
+import org.apache.maven.enforcer.rule.api.EnforcerRuleException;
+import org.apache.maven.model.Build;
+import org.apache.maven.model.DependencyManagement;
+import org.apache.maven.model.Model;
+import org.apache.maven.model.PluginManagement;
+import org.apache.maven.model.Reporting;
+import org.junit.jupiter.api.Test;
+
+import java.util.stream.Stream;
+
+import static com.solubris.enforcer.ModelStubber.dependencyOf;
+import static com.solubris.enforcer.ModelStubber.extensionOf;
+import static com.solubris.enforcer.ModelStubber.pluginOf;
+import static com.solubris.enforcer.ModelStubber.reportPluginOf;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatNoException;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+import static org.mockito.Mockito.mock;
+
+/**
+ * Test cases for UnusedPropertyRule enforcer rule.
+ */
+class UnusedPropertyRuleTest {
+
+    @Test
+    void noPropertiesPasses() {
+        Model originalModel = new Model();
+        Model effectiveModel = new Model();
+
+        UnusedPropertyRule rule = createRule(originalModel, effectiveModel);
+
+        assertThatNoException().isThrownBy(rule::execute);
+    }
+
+    @Test
+    void versionPropertyUsedByDirectDependencyPasses() {
+        Model originalModel = new Model();
+        originalModel.addProperty("junit.version", "5.9.3");
+        originalModel.addDependency(dependencyOf("org.junit", "junit", "${junit.version}"));
+
+        Model effectiveModel = new Model();
+        effectiveModel.addDependency(dependencyOf("org.junit", "junit", "5.9.3"));
+
+        UnusedPropertyRule rule = createRule(originalModel, effectiveModel);
+
+        Stream<String> violations = rule.scanProperties();
+
+        assertThat(violations).isEmpty();
+    }
+
+    @Test
+    void versionPropertyUsedByManagedDependencyPasses() {
+        Model originalModel = new Model();
+        originalModel.addProperty("junit.version", "5.9.3");
+        DependencyManagement originalDepMgmt = new DependencyManagement();
+        originalDepMgmt.addDependency(dependencyOf("org.junit", "junit", "${junit.version}"));
+        originalModel.setDependencyManagement(originalDepMgmt);
+
+        Model effectiveModel = new Model();
+        DependencyManagement effectiveDepMgmt = new DependencyManagement();
+        effectiveDepMgmt.addDependency(dependencyOf("org.junit", "junit", "5.9.3"));
+        effectiveModel.setDependencyManagement(effectiveDepMgmt);
+
+        UnusedPropertyRule rule = createRule(originalModel, effectiveModel);
+
+        Stream<String> violations = rule.scanProperties();
+
+        assertThat(violations).isEmpty();
+    }
+
+    @Test
+    void versionPropertyUsedByPluginPasses() {
+        Model originalModel = new Model();
+        originalModel.addProperty("compiler.version", "3.13.0");
+        Build originalBuild = new Build();
+        originalBuild.addPlugin(pluginOf("org.apache.maven.plugins", "maven-compiler-plugin", "${compiler.version}"));
+        originalModel.setBuild(originalBuild);
+
+        Model effectiveModel = new Model();
+        Build effectiveBuild = new Build();
+        effectiveBuild.addPlugin(pluginOf("org.apache.maven.plugins", "maven-compiler-plugin", "3.13.0"));
+        effectiveModel.setBuild(effectiveBuild);
+
+        UnusedPropertyRule rule = createRule(originalModel, effectiveModel);
+
+        Stream<String> violations = rule.scanProperties();
+
+        assertThat(violations).isEmpty();
+    }
+
+    @Test
+    void versionPropertyUsedByManagedPluginPasses() {
+        Model originalModel = new Model();
+        originalModel.addProperty("compiler.version", "3.13.0");
+        Build originalBuild = new Build();
+        PluginManagement originalPluginMgmt = new PluginManagement();
+        originalPluginMgmt.addPlugin(pluginOf("org.apache.maven.plugins", "maven-compiler-plugin", "${compiler.version}"));
+        originalBuild.setPluginManagement(originalPluginMgmt);
+        originalModel.setBuild(originalBuild);
+
+        Model effectiveModel = new Model();
+        Build effectiveBuild = new Build();
+        PluginManagement effectivePluginMgmt = new PluginManagement();
+        effectivePluginMgmt.addPlugin(pluginOf("org.apache.maven.plugins", "maven-compiler-plugin", "3.13.0"));
+        effectiveBuild.setPluginManagement(effectivePluginMgmt);
+        effectiveModel.setBuild(effectiveBuild);
+
+        UnusedPropertyRule rule = createRule(originalModel, effectiveModel);
+
+        Stream<String> violations = rule.scanProperties();
+
+        assertThat(violations).isEmpty();
+    }
+
+    @Test
+    void versionPropertyUsedByExtensionPasses() {
+        Model originalModel = new Model();
+        originalModel.addProperty("ext.version", "1.0.0");
+        Build originalBuild = new Build();
+        originalBuild.addExtension(extensionOf("org.example", "my-extension", "${ext.version}"));
+        originalModel.setBuild(originalBuild);
+
+        Model effectiveModel = new Model();
+        Build effectiveBuild = new Build();
+        effectiveBuild.addExtension(extensionOf("org.example", "my-extension", "1.0.0"));
+        effectiveModel.setBuild(effectiveBuild);
+
+        UnusedPropertyRule rule = createRule(originalModel, effectiveModel);
+
+        Stream<String> violations = rule.scanProperties();
+
+        assertThat(violations).isEmpty();
+    }
+
+    @Test
+    void versionPropertyUsedByReportPluginPasses() {
+        Model originalModel = new Model();
+        originalModel.addProperty("site.version", "4.0.0");
+        Reporting originalReporting = new Reporting();
+        originalReporting.addPlugin(reportPluginOf("org.apache.maven.plugins", "maven-site-plugin", "${site.version}"));
+        originalModel.setReporting(originalReporting);
+
+        Model effectiveModel = new Model();
+        Reporting effectiveReporting = new Reporting();
+        effectiveReporting.addPlugin(reportPluginOf("org.apache.maven.plugins", "maven-site-plugin", "4.0.0"));
+        effectiveModel.setReporting(effectiveReporting);
+
+        UnusedPropertyRule rule = createRule(originalModel, effectiveModel);
+
+        Stream<String> violations = rule.scanProperties();
+
+        assertThat(violations).isEmpty();
+    }
+
+    @Test
+    void unusedVersionPropertyFails() {
+        Model originalModel = new Model();
+        originalModel.addProperty("old-lib.version", "2.0.0");
+
+        Model effectiveModel = new Model();
+
+        UnusedPropertyRule rule = createRule(originalModel, effectiveModel);
+
+        Stream<String> violations = rule.scanProperties();
+
+        assertThat(violations)
+                .hasSize(1)
+                .first()
+                .asString()
+                .contains("old-lib.version")
+                .contains("2.0.0")
+                .contains("unused");
+    }
+
+    @Test
+    void nonVersionPropertyIsIgnored() {
+        Model originalModel = new Model();
+        originalModel.addProperty("project.build.sourceEncoding", "UTF-8");
+
+        Model effectiveModel = new Model();
+
+        UnusedPropertyRule rule = createRule(originalModel, effectiveModel);
+
+        Stream<String> violations = rule.scanProperties();
+
+        assertThat(violations).isEmpty();
+    }
+
+    @Test
+    void multiplePropertiesMixedUsage() {
+        Model originalModel = new Model();
+        originalModel.addProperty("junit.version", "5.9.3");
+        originalModel.addProperty("old-lib.version", "2.0.0");
+        originalModel.addDependency(dependencyOf("org.junit", "junit", "${junit.version}"));
+
+        Model effectiveModel = new Model();
+        effectiveModel.addDependency(dependencyOf("org.junit", "junit", "5.9.3"));
+
+        UnusedPropertyRule rule = createRule(originalModel, effectiveModel);
+
+        Stream<String> violations = rule.scanProperties();
+
+        assertThat(violations)
+                .hasSize(1)
+                .allMatch(v -> v.contains("old-lib.version"));
+    }
+
+    @Test
+    void multipleUnusedPropertiesReported() {
+        Model originalModel = new Model();
+        originalModel.addProperty("lib-a.version", "1.0.0");
+        originalModel.addProperty("lib-b.version", "2.0.0");
+
+        Model effectiveModel = new Model();
+
+        UnusedPropertyRule rule = createRule(originalModel, effectiveModel);
+
+        Stream<String> violations = rule.scanProperties();
+
+        assertThat(violations)
+                .hasSize(2)
+                .anyMatch(v -> v.contains("lib-a.version"))
+                .anyMatch(v -> v.contains("lib-b.version"));
+    }
+
+    @Test
+    void executeThrowsOnUnusedProperty() {
+        Model originalModel = new Model();
+        originalModel.addProperty("orphaned.version", "3.0.0");
+
+        Model effectiveModel = new Model();
+
+        UnusedPropertyRule rule = createRule(originalModel, effectiveModel);
+
+        assertThatThrownBy(rule::execute)
+                .isInstanceOf(EnforcerRuleException.class)
+                .hasMessageContaining("orphaned.version")
+                .hasMessageContaining("3.0.0");
+    }
+
+    @Test
+    void executePassesWhenAllPropertiesUsed() {
+        Model originalModel = new Model();
+        originalModel.addProperty("junit.version", "5.9.3");
+        originalModel.addDependency(dependencyOf("org.junit", "junit", "${junit.version}"));
+
+        Model effectiveModel = new Model();
+        effectiveModel.addDependency(dependencyOf("org.junit", "junit", "5.9.3"));
+
+        UnusedPropertyRule rule = createRule(originalModel, effectiveModel);
+
+        assertThatNoException().isThrownBy(rule::execute);
+    }
+
+    @Test
+    void versionPropertyUsedByPluginDependencyPasses() {
+        Model originalModel = new Model();
+        originalModel.addProperty("api.version", "3.0.0");
+        Build originalBuild = new Build();
+        var plugin = pluginOf("org.apache.maven.plugins", "maven-compiler-plugin", "3.13.0");
+        plugin.addDependency(dependencyOf("org.apache.maven", "maven-plugin-api", "${api.version}"));
+        originalBuild.addPlugin(plugin);
+        originalModel.setBuild(originalBuild);
+
+        Model effectiveModel = new Model();
+        Build effectiveBuild = new Build();
+        var effectivePlugin = pluginOf("org.apache.maven.plugins", "maven-compiler-plugin", "3.13.0");
+        effectivePlugin.addDependency(dependencyOf("org.apache.maven", "maven-plugin-api", "3.0.0"));
+        effectiveBuild.addPlugin(effectivePlugin);
+        effectiveModel.setBuild(effectiveBuild);
+
+        UnusedPropertyRule rule = createRule(originalModel, effectiveModel);
+
+        Stream<String> violations = rule.scanProperties();
+
+        assertThat(violations).isEmpty();
+    }
+
+    private static UnusedPropertyRule createRule(Model originalModel, Model effectiveModel) {
+        UnusedPropertyRule rule = new UnusedPropertyRule(originalModel, effectiveModel);
+        rule.setLog(mock(EnforcerLogger.class));
+        return rule;
+    }
+}