---
title: Product.SubscriptionOffer.Signature
framework: storekit
role: symbol
role_heading: Structure
path: storekit/product/subscriptionoffer/signature
---

# Product.SubscriptionOffer.Signature

A cryptographic signature for a promotional offer.

## Declaration

```swift
struct Signature
```

## Overview

Overview For information about promotional offers, see Implementing promotional offers in your app. The App Store Server Library provides a function that produces signatures for promotional offers. For more information, see Simplifying your implementation by using the App Store Server Library.

## Topics

### Creating subscription offer signatures

- [init(keyID:nonce:timestamp:signature:)](storekit/product/subscriptionoffer/signature/init(keyid:nonce:timestamp:signature:).md)

### Getting signature elements

- [keyID](storekit/product/subscriptionoffer/signature/keyid.md)
- [nonce](storekit/product/subscriptionoffer/signature/nonce.md)
- [signature](storekit/product/subscriptionoffer/signature/signature.md)
- [timestamp](storekit/product/subscriptionoffer/signature/timestamp.md)

## Relationships

### Conforms To

- [Equatable](swift/equatable.md)
- [Hashable](swift/hashable.md)
- [Sendable](swift/sendable.md)
- [SendableMetatype](swift/sendablemetatype.md)