diff --git a/apps/api-extractor/src/analyzer/ExportAnalyzer.ts b/apps/api-extractor/src/analyzer/ExportAnalyzer.ts
index 53f8c12994c..e31edd49d44 100644
--- a/apps/api-extractor/src/analyzer/ExportAnalyzer.ts
+++ b/apps/api-extractor/src/analyzer/ExportAnalyzer.ts
@@ -74,6 +74,7 @@ export class ExportAnalyzer {
   private readonly _importableAmbientSourceFiles: Set<ts.SourceFile> = new Set<ts.SourceFile>();
 
   private readonly _astImportsByKey: Map<string, AstImport> = new Map<string, AstImport>();
+  private readonly _astImportInternalsByAstModule: Map<AstModule, AstImportInternal> = new Map<AstModule, AstImportInternal>();
 
   public constructor(program: ts.Program, typeChecker: ts.TypeChecker, bundledPackageNames: Set<string>,
     astSymbolTable: IAstSymbolTable) {
@@ -452,11 +453,16 @@ export class ExportAnalyzer {
 
         if (externalModulePath === undefined) {
           const astModule: AstModule = this._fetchSpecifierAstModule(importDeclaration, declarationSymbol);
-          return new AstImportInternal({
-            importKind: AstImportInternalKind.StarImport,
-            exportName: declarationSymbol.name,
-            astModule: astModule
-          });
+          let astImportInternal: AstImportInternal | undefined = this._astImportInternalsByAstModule.get(astModule);
+          if (!astImportInternal) {
+            astImportInternal = new AstImportInternal({
+              importKind: AstImportInternalKind.StarImport,
+              exportName: declarationSymbol.name,
+              astModule: astModule
+            });
+            this._astImportInternalsByAstModule.set(astModule, astImportInternal);
+          }
+          return astImportInternal;
         }
 
         // Here importSymbol=undefined because {@inheritDoc} and such are not going to work correctly for
diff --git a/apps/api-extractor/src/generators/DtsRollupGenerator.ts b/apps/api-extractor/src/generators/DtsRollupGenerator.ts
index eb9b4d9a60f..7682fdaf722 100644
--- a/apps/api-extractor/src/generators/DtsRollupGenerator.ts
+++ b/apps/api-extractor/src/generators/DtsRollupGenerator.ts
@@ -20,6 +20,7 @@ import { StringWriter } from './StringWriter';
 import { DtsEmitHelpers } from './DtsEmitHelpers';
 import { DeclarationMetadata } from '../collector/DeclarationMetadata';
 import { AstImportInternal } from '../analyzer/AstImportInternal';
+import { AstModuleExportInfo } from '../analyzer/AstModule';
 
 /**
  * Used with DtsRollupGenerator.writeTypingsFile()
@@ -133,10 +134,7 @@ export class DtsRollupGenerator {
           }
         }
       } else if (entity.astEntity instanceof AstImportInternal) {
-        if (!entity.astEntity.astModule.astModuleExportInfo) {
-          // This should never happen
-          throw new InternalError('local imported module has not been parsed.');
-        }
+        const astModuleExportInfo: AstModuleExportInfo = collector.astSymbolTable.fetchAstModuleExportInfo(entity.astEntity.astModule);
         if (!entity.nameForEmit) {
           // This should never happen
           throw new InternalError('referencedEntry.nameForEmit is undefined');
@@ -150,7 +148,7 @@ export class DtsRollupGenerator {
 
         // all local exports of local imported module are just references to top-level declarations
         stringWriter.writeLine('  export {');
-        entity.astEntity.astModule.astModuleExportInfo.exportedLocalEntities.forEach((exportedEntity, exportedName) => {
+        astModuleExportInfo.exportedLocalEntities.forEach((exportedEntity, exportedName) => {
           const collectorEntity: CollectorEntity | undefined = collector.tryGetCollectorEntity(exportedEntity);
           if (!collectorEntity) {
             // This should never happen
@@ -165,6 +163,10 @@ export class DtsRollupGenerator {
         });
         stringWriter.writeLine('  }'); // end of "export { ... }"
 
+        if (astModuleExportInfo.starExportedExternalModules.size > 0) {
+          throw new Error(`Unsupported star export of external module inside namespace imported module: ${entity.nameForEmit}`);
+        }
+
         stringWriter.writeLine('}'); // end of "declare namespace { ... }"
       }