diff --git a/deno/lib/__tests__/partials.test.ts b/deno/lib/__tests__/partials.test.ts
index 06fb29ba8..1825753a9 100644
--- a/deno/lib/__tests__/partials.test.ts
+++ b/deno/lib/__tests__/partials.test.ts
@@ -185,20 +185,6 @@ test("required with mask", () => {
   expect(requiredObject.shape.country).toBeInstanceOf(z.ZodOptional);
 });
 
-test("required with mask containing a nonexistent key", () => {
-  const object = z.object({
-    name: z.string(),
-    age: z.number().optional(),
-    field: z.string().optional().default("asdf"),
-    country: z.string().optional(),
-  });
-  object.required({
-    age: true,
-    // @ts-expect-error should not accept unexpected keys.
-    doesntExist: true,
-  });
-});
-
 test("required with mask -- ignore falsy values", () => {
   const object = z.object({
     name: z.string(),
@@ -256,21 +242,6 @@ test("partial with mask -- ignore falsy values", async () => {
   await masked.parseAsync({ country: "US" });
 });
 
-test("partial with mask containing a nonexistent key", () => {
-  const object = z.object({
-    name: z.string(),
-    age: z.number().optional(),
-    field: z.string().optional().default("asdf"),
-    country: z.string().optional(),
-  });
-
-  object.partial({
-    age: true,
-    // @ts-expect-error should not accept unexpected keys.
-    doesntExist: true,
-  });
-});
-
 test("deeppartial array", () => {
   const schema = z.object({ array: z.string().array().min(42) }).deepPartial();
 
diff --git a/deno/lib/types.ts b/deno/lib/types.ts
index d9aecc9c5..7b3ee92cb 100644
--- a/deno/lib/types.ts
+++ b/deno/lib/types.ts
@@ -2182,8 +2182,6 @@ export type SomeZodObject = ZodObject<
   ZodTypeAny
 >;
 
-export type objectKeyMask<Obj> = { [k in keyof Obj]?: true };
-
 export type noUnrecognized<Obj extends object, Shape extends object> = {
   [k in keyof Obj]: k extends keyof Shape ? Obj[k] : never;
 };
@@ -2550,8 +2548,8 @@ export class ZodObject<
     }) as any;
   }
 
-  pick<Mask extends objectKeyMask<T>>(
-    mask: noUnrecognized<Mask, T>
+  pick<Mask extends { [k in keyof T]?: true }>(
+    mask: Mask
   ): ZodObject<Pick<T, Extract<keyof T, keyof Mask>>, UnknownKeys, Catchall> {
     const shape: any = {};
 
@@ -2567,8 +2565,8 @@ export class ZodObject<
     }) as any;
   }
 
-  omit<Mask extends objectKeyMask<T>>(
-    mask: noUnrecognized<Mask, objectKeyMask<T>>
+  omit<Mask extends { [k in keyof T]?: true }>(
+    mask: Mask
   ): ZodObject<Omit<T, keyof Mask>, UnknownKeys, Catchall> {
     const shape: any = {};
 
@@ -2596,8 +2594,8 @@ export class ZodObject<
     UnknownKeys,
     Catchall
   >;
-  partial<Mask extends objectKeyMask<T>>(
-    mask: noUnrecognized<Mask, objectKeyMask<T>>
+  partial<Mask extends { [k in keyof T]?: true }>(
+    mask: Mask
   ): ZodObject<
     objectUtil.noNever<{
       [k in keyof T]: k extends keyof Mask ? ZodOptional<T[k]> : T[k];
@@ -2629,8 +2627,8 @@ export class ZodObject<
     UnknownKeys,
     Catchall
   >;
-  required<Mask extends objectKeyMask<T>>(
-    mask: noUnrecognized<Mask, objectKeyMask<T>>
+  required<Mask extends { [k in keyof T]?: true }>(
+    mask: Mask
   ): ZodObject<
     objectUtil.noNever<{
       [k in keyof T]: k extends keyof Mask ? deoptional<T[k]> : T[k];
diff --git a/playground.ts b/playground.ts
index 24fb4f8f8..d17b18eb4 100644
--- a/playground.ts
+++ b/playground.ts
@@ -1,8 +1,2 @@
 import { z } from "./src";
-
-function foo<Schema extends z.AnyZodObject>(schema: Schema) {
-  return z.object({ bar: schema }).transform((x) => x.bar);
-  //                                                   ^^^
-  // Property 'bar' does not exist on type
-  // '{ [k in keyof baseObjectOutputType<{ bar: Schema; }>]: baseObjectOutputType<{ bar: Schema; }>[k]; }'.
-}
+z;
diff --git a/src/__tests__/partials.test.ts b/src/__tests__/partials.test.ts
index d716b4471..3186c9f97 100644
--- a/src/__tests__/partials.test.ts
+++ b/src/__tests__/partials.test.ts
@@ -184,20 +184,6 @@ test("required with mask", () => {
   expect(requiredObject.shape.country).toBeInstanceOf(z.ZodOptional);
 });
 
-test("required with mask containing a nonexistent key", () => {
-  const object = z.object({
-    name: z.string(),
-    age: z.number().optional(),
-    field: z.string().optional().default("asdf"),
-    country: z.string().optional(),
-  });
-  object.required({
-    age: true,
-    // @ts-expect-error should not accept unexpected keys.
-    doesntExist: true,
-  });
-});
-
 test("required with mask -- ignore falsy values", () => {
   const object = z.object({
     name: z.string(),
@@ -255,21 +241,6 @@ test("partial with mask -- ignore falsy values", async () => {
   await masked.parseAsync({ country: "US" });
 });
 
-test("partial with mask containing a nonexistent key", () => {
-  const object = z.object({
-    name: z.string(),
-    age: z.number().optional(),
-    field: z.string().optional().default("asdf"),
-    country: z.string().optional(),
-  });
-
-  object.partial({
-    age: true,
-    // @ts-expect-error should not accept unexpected keys.
-    doesntExist: true,
-  });
-});
-
 test("deeppartial array", () => {
   const schema = z.object({ array: z.string().array().min(42) }).deepPartial();
 
diff --git a/src/types.ts b/src/types.ts
index 718d082e1..81c2dcde5 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -2182,8 +2182,6 @@ export type SomeZodObject = ZodObject<
   ZodTypeAny
 >;
 
-export type objectKeyMask<Obj> = { [k in keyof Obj]?: true };
-
 export type noUnrecognized<Obj extends object, Shape extends object> = {
   [k in keyof Obj]: k extends keyof Shape ? Obj[k] : never;
 };
@@ -2550,8 +2548,8 @@ export class ZodObject<
     }) as any;
   }
 
-  pick<Mask extends objectKeyMask<T>>(
-    mask: noUnrecognized<Mask, T>
+  pick<Mask extends { [k in keyof T]?: true }>(
+    mask: Mask
   ): ZodObject<Pick<T, Extract<keyof T, keyof Mask>>, UnknownKeys, Catchall> {
     const shape: any = {};
 
@@ -2567,8 +2565,8 @@ export class ZodObject<
     }) as any;
   }
 
-  omit<Mask extends objectKeyMask<T>>(
-    mask: noUnrecognized<Mask, objectKeyMask<T>>
+  omit<Mask extends { [k in keyof T]?: true }>(
+    mask: Mask
   ): ZodObject<Omit<T, keyof Mask>, UnknownKeys, Catchall> {
     const shape: any = {};
 
@@ -2596,8 +2594,8 @@ export class ZodObject<
     UnknownKeys,
     Catchall
   >;
-  partial<Mask extends objectKeyMask<T>>(
-    mask: noUnrecognized<Mask, objectKeyMask<T>>
+  partial<Mask extends { [k in keyof T]?: true }>(
+    mask: Mask
   ): ZodObject<
     objectUtil.noNever<{
       [k in keyof T]: k extends keyof Mask ? ZodOptional<T[k]> : T[k];
@@ -2629,8 +2627,8 @@ export class ZodObject<
     UnknownKeys,
     Catchall
   >;
-  required<Mask extends objectKeyMask<T>>(
-    mask: noUnrecognized<Mask, objectKeyMask<T>>
+  required<Mask extends { [k in keyof T]?: true }>(
+    mask: Mask
   ): ZodObject<
     objectUtil.noNever<{
       [k in keyof T]: k extends keyof Mask ? deoptional<T[k]> : T[k];