diff --git a/types/jsdom/jsdom-tests.ts b/types/jsdom/jsdom-tests.ts
index 1420723b8d..0b8be95052 100644
--- a/types/jsdom/jsdom-tests.ts
+++ b/types/jsdom/jsdom-tests.ts
@@ -1,4 +1,4 @@
-import { JSDOM, VirtualConsole, CookieJar, FromUrlOptions, FromFileOptions, DOMWindow, ResourceLoader, FetchOptions } from 'jsdom';
+import { JSDOM, VirtualConsole, CookieJar, FromUrlOptions, FromFileOptions, DOMWindow, ResourceLoader, FetchOptions, ConstructorOptions } from 'jsdom';
 import { CookieJar as ToughCookieJar, MemoryCookieStore } from 'tough-cookie';
 import { Script } from 'vm';
 
@@ -56,8 +56,9 @@ function test_cookieJar() {
     const store = {} as MemoryCookieStore;
     const options = {} as ToughCookieJar.Options;
 
-    const cookieJar = new CookieJar(store, options);
-    const dom = new JSDOM(``, { cookieJar });
+    const cookieJar: CookieJar = new CookieJar(store, options);
+    const constructorOptions: ConstructorOptions = { cookieJar };
+    const dom = new JSDOM(``, constructorOptions);
 }
 
 function test_beforeParse() {
diff --git a/types/request/request-tests.ts b/types/request/request-tests.ts
index 1d13dcbaaa..66163d5863 100644
--- a/types/request/request-tests.ts
+++ b/types/request/request-tests.ts
@@ -14,7 +14,6 @@ let strOrTrueOrUndef: string | true | undefined;
 const buffer: Buffer = new Buffer('foo');
 let num = 0;
 let bool: boolean;
-let date: Date;
 let obj: object;
 const dest = 'foo';
 
@@ -58,8 +57,8 @@ obj = req.toJSON();
 let cookie: request.Cookie = request.cookie('foo')!;
 str = cookie.key;
 str = cookie.value;
-date = cookie.expires;
-str = cookie.path;
+const expires: Date | 'Infinity' = cookie.expires;
+const cpath: string | null = cookie.path;
 str = cookie.toString();
 bool = cookie.httpOnly;
 
diff --git a/types/tough-cookie/index.d.ts b/types/tough-cookie/index.d.ts
index e68496d302..c432e01aa2 100644
--- a/types/tough-cookie/index.d.ts
+++ b/types/tough-cookie/index.d.ts
@@ -73,18 +73,16 @@ export class Cookie {
 
     constructor(properties?: Cookie.Properties);
 
-    // TODO: Some of the following properties might actually be nullable.
-
     key: string;
     value: string;
-    expires: Date;
+    expires: Date | 'Infinity';
     maxAge: number | 'Infinity' | '-Infinity';
-    domain: string;
-    path: string;
+    domain: string | null;
+    path: string | null;
     secure: boolean;
     httpOnly: boolean;
-    extensions: string[];
-    creation: Date;
+    extensions: string[] | null;
+    creation: Date | null;
     creationIndex: number;
 
     hostOnly: boolean | null;