diff --git a/src/FileHandler.ts b/src/FileHandler.ts
index 9f05e52..099306f 100644
--- a/src/FileHandler.ts
+++ b/src/FileHandler.ts
@@ -4,6 +4,8 @@ interface FileHandler {
   getModule(
     filename: string | null | undefined
   ): LicenseIdentifiedModule | null;
+  isBuildRoot(filename: string): boolean;
+  isInModuleDirectory(filename: string): boolean;
 }
 
 export { FileHandler };
diff --git a/src/LicenseIdentifiedModule.ts b/src/LicenseIdentifiedModule.ts
index 8e5966d..be396b2 100644
--- a/src/LicenseIdentifiedModule.ts
+++ b/src/LicenseIdentifiedModule.ts
@@ -2,9 +2,9 @@ import { Module } from './Module';
 import { PackageJson } from './PackageJson';
 
 interface LicenseIdentifiedModule extends Module {
-  packageJson: PackageJson;
-  licenseId: string | null;
-  licenseText: string | null;
+  packageJson?: PackageJson;
+  licenseId?: string | null;
+  licenseText?: string | null;
 }
 
 export { LicenseIdentifiedModule };
diff --git a/src/PluginChunkReadHandler.ts b/src/PluginChunkReadHandler.ts
index 436b930..25f7799 100644
--- a/src/PluginChunkReadHandler.ts
+++ b/src/PluginChunkReadHandler.ts
@@ -1,7 +1,8 @@
 import { WebpackChunkHandler } from './WebpackChunkHandler';
 import { WebpackChunk } from './WebpackChunk';
+import { WebpackChunkModule } from './WebpackChunkModule';
 import { WebpackChunkModuleIterator } from './WebpackChunkModuleIterator';
-import { WebpackModuleFileIterator } from './WebpackModuleFileIterator';
+import { WebpackInnerModuleIterator } from './WebpackInnerModuleIterator';
 import { FileHandler } from './FileHandler';
 import { LicenseTypeIdentifier } from './LicenseTypeIdentifier';
 import { FileSystem } from './FileSystem';
@@ -9,7 +10,6 @@ import { PackageJson } from './PackageJson';
 import { LicenseTextReader } from './LicenseTextReader';
 import { ModuleCache } from './ModuleCache';
 import { LicensePolicy } from './LicensePolicy';
-import { Module } from './Module';
 import { LicenseIdentifiedModule } from './LicenseIdentifiedModule';
 import { WebpackCompilation } from './WebpackCompilation';
 import { Logger } from './Logger';
@@ -17,7 +17,7 @@ import { WebpackStats } from './WebpackStats';
 
 class PluginChunkReadHandler implements WebpackChunkHandler {
   private moduleIterator = new WebpackChunkModuleIterator();
-  private fileIterator = new WebpackModuleFileIterator(require.resolve);
+  private innerModuleIterator = new WebpackInnerModuleIterator(require.resolve);
 
   constructor(
     private logger: Logger,
@@ -34,15 +34,51 @@ class PluginChunkReadHandler implements WebpackChunkHandler {
     moduleCache: ModuleCache,
     stats: WebpackStats | undefined
   ) {
-    this.moduleIterator.iterateModules(compilation, chunk, stats, module => {
-      this.fileIterator.iterateFiles(
-        module,
-        (filename: string | null | undefined) => {
-          const module = this.fileHandler.getModule(filename);
-          this.processModule(compilation, chunk, moduleCache, module);
-        }
-      );
-    });
+    this.moduleIterator.iterateModules(
+      compilation,
+      chunk,
+      stats,
+      chunkModule => {
+        this.innerModuleIterator.iterateModules(
+          chunkModule,
+          (module: WebpackChunkModule) => {
+            const identifiedModule =
+              this.extractIdentifiedModule(module) ||
+              this.fileHandler.getModule(module.resource);
+            if (identifiedModule) {
+              this.processModule(
+                compilation,
+                chunk,
+                moduleCache,
+                identifiedModule
+              );
+            }
+          }
+        );
+      }
+    );
+  }
+
+  private extractIdentifiedModule(
+    module: WebpackChunkModule
+  ): LicenseIdentifiedModule | undefined {
+    const resolved = module.resourceResolveData;
+    if (!resolved) return undefined;
+    const {
+      descriptionFileRoot: directory,
+      descriptionFileData: packageJson
+    } = resolved;
+    if (
+      this.fileHandler.isInModuleDirectory(directory) &&
+      !this.fileHandler.isBuildRoot(directory)
+    ) {
+      return {
+        directory,
+        packageJson,
+        name: packageJson.name
+      };
+    }
+    return undefined;
   }
 
   private getPackageJson(directory: string): PackageJson {
@@ -54,20 +90,17 @@ class PluginChunkReadHandler implements WebpackChunkHandler {
     compilation: WebpackCompilation,
     chunk: WebpackChunk,
     moduleCache: ModuleCache,
-    module: Module | LicenseIdentifiedModule | null
+    module: LicenseIdentifiedModule
   ) {
-    if (module && !moduleCache.alreadySeenForChunk(chunk.name, module.name)) {
+    if (!moduleCache.alreadySeenForChunk(chunk.name, module.name)) {
       const alreadyIncludedModule = moduleCache.getModule(module.name);
       if (alreadyIncludedModule !== null) {
         moduleCache.registerModule(chunk.name, alreadyIncludedModule);
       } else {
         // module not yet in cache
-        const packageJson: PackageJson =
-          (<LicenseIdentifiedModule>module).packageJson ??
-          this.getPackageJson(module.directory);
-        const licenseType:
-          | string
-          | null = this.licenseTypeIdentifier.findLicenseIdentifier(
+        const packageJson =
+          module.packageJson ?? this.getPackageJson(module.directory);
+        const licenseType = this.licenseTypeIdentifier.findLicenseIdentifier(
           compilation,
           module.name,
           packageJson
diff --git a/src/PluginFileHandler.ts b/src/PluginFileHandler.ts
index 2de7ec8..789923b 100644
--- a/src/PluginFileHandler.ts
+++ b/src/PluginFileHandler.ts
@@ -20,28 +20,30 @@ class PluginFileHandler implements FileHandler {
       : this.cache[filename];
   }
 
+  isInModuleDirectory(filename: string) {
+    if (this.modulesDirectories === null) return true;
+    if (filename === null || filename === undefined) return false;
+    let foundInModuleDirectory = false;
+    const resolvedPath = this.fileSystem.resolvePath(filename);
+    for (const modulesDirectory of this.modulesDirectories) {
+      if (
+        resolvedPath.startsWith(this.fileSystem.resolvePath(modulesDirectory))
+      ) {
+        foundInModuleDirectory = true;
+      }
+    }
+    return foundInModuleDirectory;
+  }
+
+  isBuildRoot(filename: string) {
+    return this.buildRoot === filename;
+  }
+
   private getModuleInternal(
     filename: string
   ): Partial<LicenseIdentifiedModule> | null {
-    if (filename === null || filename === undefined) {
-      return null;
-    }
-
-    if (this.modulesDirectories !== null) {
-      let foundInModuleDirectory = false;
-      for (const modulesDirectory of this.modulesDirectories) {
-        if (
-          this.fileSystem
-            .resolvePath(filename)
-            .startsWith(this.fileSystem.resolvePath(modulesDirectory))
-        ) {
-          foundInModuleDirectory = true;
-        }
-      }
-      if (!foundInModuleDirectory) {
-        return null;
-      }
-    }
+    if (filename === null || filename === undefined) return null;
+    if (!this.isInModuleDirectory(filename)) return null;
 
     const module = this.findModuleDir(filename);
 
@@ -78,7 +80,7 @@ class PluginFileHandler implements FileHandler {
       }
     }
 
-    if (this.buildRoot === dirOfModule) {
+    if (this.isBuildRoot(dirOfModule)) {
       return null;
     }
 
diff --git a/src/WebpackChunkHandler.ts b/src/WebpackChunkHandler.ts
index 830b858..e9597e9 100644
--- a/src/WebpackChunkHandler.ts
+++ b/src/WebpackChunkHandler.ts
@@ -1,6 +1,6 @@
 import { WebpackChunk } from './WebpackChunk';
 import { ModuleCache } from './ModuleCache';
-import { Module } from './Module';
+import { LicenseIdentifiedModule } from './LicenseIdentifiedModule';
 import { WebpackCompilation } from './WebpackCompilation';
 import { WebpackStats } from './WebpackStats';
 
@@ -15,7 +15,7 @@ interface WebpackChunkHandler {
     compilation: WebpackCompilation,
     chunk: WebpackChunk,
     moduleCache: ModuleCache,
-    module: Module
+    module: LicenseIdentifiedModule
   ): void;
 }
 
diff --git a/src/WebpackChunkModule.ts b/src/WebpackChunkModule.ts
index fd86b50..63bee64 100644
--- a/src/WebpackChunkModule.ts
+++ b/src/WebpackChunkModule.ts
@@ -1,5 +1,7 @@
+import { PackageJson } from './PackageJson';
+
 export interface WebpackChunkModule {
-  resource: string;
+  resource?: string;
   rootModule?: {
     resource?: string;
   };
@@ -8,4 +10,8 @@ export interface WebpackChunkModule {
   };
   fileDependencies?: string[];
   dependencies?: WebpackChunkModule[];
+  resourceResolveData?: {
+    descriptionFileRoot: string;
+    descriptionFileData: PackageJson;
+  };
 }
diff --git a/src/WebpackFileSystem.ts b/src/WebpackFileSystem.ts
index 07f5708..c916095 100644
--- a/src/WebpackFileSystem.ts
+++ b/src/WebpackFileSystem.ts
@@ -18,8 +18,8 @@ class WebpackFileSystem implements FileSystem {
 
   pathExists(filename: string): boolean {
     try {
-      this.fs.statSync(filename);
-      return true;
+      const stat = this.fs.statSync(filename, { throwIfNoEntry: false });
+      return !!stat;
     } catch (e) {
       return false;
     }
@@ -44,7 +44,7 @@ class WebpackFileSystem implements FileSystem {
   isDirectory(dir: string): boolean {
     let isDir = false;
     try {
-      isDir = this.fs.statSync(dir).isDirectory();
+      isDir = this.fs.statSync(dir, { throwIfNoEntry: false }).isDirectory();
     } catch (e) {}
     return isDir;
   }
diff --git a/src/WebpackModuleFileIterator.ts b/src/WebpackInnerModuleIterator.ts
similarity index 74%
rename from src/WebpackModuleFileIterator.ts
rename to src/WebpackInnerModuleIterator.ts
index aa3a565..198f3e2 100644
--- a/src/WebpackModuleFileIterator.ts
+++ b/src/WebpackInnerModuleIterator.ts
@@ -1,35 +1,37 @@
 import { WebpackChunkModule } from './WebpackChunkModule';
 
-class WebpackModuleFileIterator {
+class WebpackInnerModuleIterator {
   constructor(private requireResolve: RequireResolve) {}
 
-  iterateFiles(
+  iterateModules(
     chunkModule: WebpackChunkModule,
-    callback: (filename: string | null | undefined) => void
+    callback: (module: WebpackChunkModule) => void
   ) {
     const internalCallback = this.internalCallback.bind(this, callback);
     internalCallback(
-      chunkModule.resource ||
-        (chunkModule.rootModule && chunkModule.rootModule.resource)
+      chunkModule.resource ? chunkModule : chunkModule.rootModule
     );
     if (Array.isArray(chunkModule.fileDependencies)) {
       const fileDependencies: string[] = chunkModule.fileDependencies;
-      fileDependencies.forEach(internalCallback);
+      fileDependencies.forEach(fileDependency =>
+        internalCallback({ resource: fileDependency })
+      );
     }
     if (Array.isArray(chunkModule.dependencies)) {
       chunkModule.dependencies.forEach(module =>
-        internalCallback(module.originModule && module.originModule.resource)
+        internalCallback(module.originModule)
       );
     }
   }
 
   private internalCallback(
-    callback: (filename: string | null | undefined) => void,
-    filename: string | null | undefined
+    callback: (module: WebpackChunkModule) => void,
+    module: WebpackChunkModule | undefined
   ): void {
-    const actualFileName = this.getActualFilename(filename);
+    if (!module) return;
+    const actualFileName = this.getActualFilename(module.resource);
     if (actualFileName) {
-      callback(actualFileName);
+      callback({ ...module, resource: actualFileName });
     }
   }
 
@@ -69,4 +71,4 @@ class WebpackModuleFileIterator {
   }
 }
 
-export { WebpackModuleFileIterator };
+export { WebpackInnerModuleIterator };
diff --git a/src/__tests__/WebpackModuleFileIterator.test.ts b/src/__tests__/WebpackInnerModuleIterator.test.ts
similarity index 93%
rename from src/__tests__/WebpackModuleFileIterator.test.ts
rename to src/__tests__/WebpackInnerModuleIterator.test.ts
index 35dda1a..7ef682a 100644
--- a/src/__tests__/WebpackModuleFileIterator.test.ts
+++ b/src/__tests__/WebpackInnerModuleIterator.test.ts
@@ -1,12 +1,12 @@
-import { WebpackModuleFileIterator } from '../WebpackModuleFileIterator';
+import { WebpackInnerModuleIterator } from '../WebpackInnerModuleIterator';
 import {
   fakeRequireResolve,
   FAKE_REQUIRE_RESOLVE_OUTPUT
 } from './FakeRequireResolve';
 
-const iterator = new WebpackModuleFileIterator(fakeRequireResolve);
+const iterator = new WebpackInnerModuleIterator(fakeRequireResolve);
 
-describe('WebpackModuleFileIterator', () => {
+describe('WebpackInnerModuleIterator', () => {
   it('returns null for falsy filename', () => {
     expect(iterator.getActualFilename('')).toBeNull();
     expect(iterator.getActualFilename(null)).toBeNull();