diff --git a/packages/core/schematics/migrations/missing-injectable/transform.ts b/packages/core/schematics/migrations/missing-injectable/transform.ts
index 8a1fd27d33cc3..e124184906877 100644
--- a/packages/core/schematics/migrations/missing-injectable/transform.ts
+++ b/packages/core/schematics/migrations/missing-injectable/transform.ts
@@ -123,6 +123,14 @@ export class MissingInjectableTransform {
     this.visitedProviderClasses.add(node);
 
     const sourceFile = node.getSourceFile();
+
+    // We cannot migrate provider classes outside of source files. This is because the
+    // migration for third-party library files should happen in "ngcc", and in general
+    // would also involve metadata parsing.
+    if (sourceFile.isDeclarationFile) {
+      return;
+    }
+
     const ngDecorators =
         node.decorators ? getAngularDecorators(this.typeChecker, node.decorators) : null;
 
diff --git a/packages/core/schematics/test/missing_injectable_migration_spec.ts b/packages/core/schematics/test/missing_injectable_migration_spec.ts
index 75dbe9b86ce80..f9526300c2bcc 100644
--- a/packages/core/schematics/test/missing_injectable_migration_spec.ts
+++ b/packages/core/schematics/test/missing_injectable_migration_spec.ts
@@ -380,7 +380,6 @@ describe('Missing injectable migration', () => {
           .toContain(`{ ${type}, Injectable } from '@angular/core`);
     });
 
-
     it(`should migrate multiple nested providers in same ${type}`, async() => {
       writeFile('/index.ts', `
         import {${type}} from '@angular/core';
@@ -689,5 +688,24 @@ describe('Missing injectable migration', () => {
       expect(tree.readContent('/service.ts'))
           .toMatch(/import { Inject, Injectable } from '@angular\/core';/);
     });
+
+    it('should not migrate provider classes in library type definitions', async() => {
+      writeFile('/node_modules/my-lib/index.d.ts', `
+        export declare class MyService {}
+      `);
+
+      writeFile('/index.ts', `
+        import {MyService} from 'my-lib';
+        import {Pipe, ${type}} from '@angular/core';
+                  
+        @${type}({${propName}: [MyService]})
+        export class TestClass {}
+      `);
+
+      await runMigration();
+
+      expect(warnOutput.length).toBe(0);
+      expect(tree.readContent('/node_modules/my-lib/index.d.ts')).not.toContain('@Injectable');
+    });
   }
 });