diff --git a/src/observable.ts b/src/observable.ts
index fc1861bc5..9272a3e22 100644
--- a/src/observable.ts
+++ b/src/observable.ts
@@ -35,16 +35,12 @@ function createObservable<T>(value: T, makePrimitive: boolean): Observable<T> |
 export type MaybePromiseObservable<T> = Observable<MaybePromise<T>>;
 
 export function observable<T>(): MaybePromiseObservable<T | undefined>;
-export function observable<T>(value: Promise<T>): MaybePromiseObservable<Promise<T>>;
-export function observable<T>(value?: Promise<T>): MaybePromiseObservable<Promise<T> | undefined>;
 export function observable<T>(value: T): MaybePromiseObservable<T>;
 export function observable<T>(value?: T): MaybePromiseObservable<T | undefined> {
     return createObservable(value, /*makePrimitive*/ false);
 }
 
 export function observablePrimitive<T>(): ObservablePrimitive<MaybePromise<T | undefined>>;
-export function observablePrimitive<T>(value: Promise<T>): ObservablePrimitive<MaybePromise<Promise<T>>>;
-export function observablePrimitive<T>(value?: Promise<T>): ObservablePrimitive<MaybePromise<Promise<T>> | undefined>;
 export function observablePrimitive<T>(value: T): ObservablePrimitive<MaybePromise<T>>;
 export function observablePrimitive<T>(value?: T): ObservablePrimitive<MaybePromise<T | undefined>> {
     return createObservable(value, /*makePrimitive*/ true);
diff --git a/tests/tests.test.ts b/tests/tests.test.ts
index a3634a970..3d9822d8b 100644
--- a/tests/tests.test.ts
+++ b/tests/tests.test.ts
@@ -2195,7 +2195,7 @@ describe('Promise values', () => {
     test('when callback works with promises', async () => {
         let resolver: (value: number) => void;
         const promise = new Promise<number>((resolve) => (resolver = resolve));
-        const obs = observable<number>(promise);
+        const obs = observable(promise);
         let didWhen = false;
         when(obs, () => {
             didWhen = true;
@@ -2208,7 +2208,7 @@ describe('Promise values', () => {
     test('when works with promises', async () => {
         let resolver: (value: number) => void;
         const promise = new Promise<number>((resolve) => (resolver = resolve));
-        const obs = observable<number>(promise);
+        const obs = observable(promise);
         let didWhen = false;
         when(obs).then(() => {
             didWhen = true;
@@ -2564,7 +2564,7 @@ describe('Locking', () => {
 });
 describe('Primitive <-> Object', () => {
     test('Starting as undefined', () => {
-        const obs = observable<{ test: string }>(undefined);
+        const obs = observable<{ test: string } | undefined>(undefined);
         expect(obs.get()).toEqual(undefined);
         obs.set({ test: 'hi' });
         expect(obs.get()).toEqual({ test: 'hi' });