diff --git a/types/is-date-object/index.d.ts b/types/is-date-object/index.d.ts
index 7d22927284..08885dce51 100644
--- a/types/is-date-object/index.d.ts
+++ b/types/is-date-object/index.d.ts
@@ -2,10 +2,7 @@
 // Project: https://github.com/ljharb/is-date-object
 // Definitions by:  Adam Zerella <https://github.com/adamzerella>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
-// TypeScript Version: 3.0
 
-declare function isDateObject(value: Date): true;
-declare function isDateObject(value?: object): boolean;
-declare function isDateObject(value?: null | boolean | string | number): false;
+declare function isDateObject(value?: any): boolean;
 
 export = isDateObject;
diff --git a/types/is-date-object/package.json b/types/is-date-object/package.json
deleted file mode 100644
index 9e02feea42..0000000000
--- a/types/is-date-object/package.json
+++ /dev/null
@@ -1,7 +0,0 @@
-{
-    "private": true,
-    "types": "index",
-    "typesVersions": {
-        ">=3.1.0-0": { "*": ["ts3.1/*"] }
-    }
-}
\ No newline at end of file
diff --git a/types/is-date-object/ts3.1/index.d.ts b/types/is-date-object/ts3.1/index.d.ts
deleted file mode 100644
index 3d09650996..0000000000
--- a/types/is-date-object/ts3.1/index.d.ts
+++ /dev/null
@@ -1,5 +0,0 @@
-declare function isDateObject(value: Date): true;
-declare function isDateObject(value?: object): boolean;
-declare function isDateObject(value?: null | boolean | string | number | symbol | bigint | []): false;
-
-export = isDateObject;
diff --git a/types/is-date-object/ts3.1/is-date-object-tests.ts b/types/is-date-object/ts3.1/is-date-object-tests.ts
deleted file mode 100644
index 9946c42d54..0000000000
--- a/types/is-date-object/ts3.1/is-date-object-tests.ts
+++ /dev/null
@@ -1,15 +0,0 @@
-import isDate = require("is-date-object");
-
-isDate();
-isDate(undefined);
-isDate(null);
-isDate(false);
-isDate(true);
-isDate(42);
-isDate('foo');
-isDate((): void => {});
-isDate([]);
-isDate({});
-isDate(/a/g);
-isDate(new RegExp('a', 'g'));
-isDate(new Date());
diff --git a/types/is-date-object/ts3.1/tsconfig.json b/types/is-date-object/ts3.1/tsconfig.json
deleted file mode 100644
index 7a40c93489..0000000000
--- a/types/is-date-object/ts3.1/tsconfig.json
+++ /dev/null
@@ -1,25 +0,0 @@
-{
-    "compilerOptions": {
-      "module": "commonjs",
-      "lib": [
-        "es6"
-      ],
-      "noImplicitAny": true,
-      "noImplicitThis": true,
-      "strictNullChecks": true,
-      "strictFunctionTypes": true,
-      "baseUrl": "../../",
-      "typeRoots": [
-        "../../"
-      ],
-      "types": [
-
-      ],
-      "noEmit": true,
-      "forceConsistentCasingInFileNames": true
-    },
-    "files": [
-      "index.d.ts",
-      "is-date-object-tests.ts"
-    ]
-}
diff --git a/types/is-date-object/ts3.1/tslint.json b/types/is-date-object/ts3.1/tslint.json
deleted file mode 100644
index e60c15844f..0000000000
--- a/types/is-date-object/ts3.1/tslint.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-    "extends": "dtslint/dt.json"
-}
\ No newline at end of file