---
title: signature
framework: storekit
role: symbol
role_heading: Instance Property
path: storekit/skadimpression/signature
---

# signature

The advertising network’s cryptographic signature for the ad impression.

## Declaration

```swift
var signature: String { get set }
```

## Mentioned in

Generating the signature to validate view-through ads Signing and providing ads

## Discussion

Discussion The ad network creates a cryptographic signature that it uses to sign ads. For instructions on generating this value, see Generating the signature to validate view-through ads.