---
title: "signature(for:using:)"
framework: passkit
role: symbol
role_heading: Instance Method
path: "passkit/jpkipasscontents/identity/signature(for:using:)-4l8jw"
---

# signature(for:using:)

Signs the supplied data with the identity’s private key

## Declaration

```swift
func signature(for data: Data, using request: JPKIPassContents.AuthenticationRequest<Self.IdentityType>) async throws -> JPKIPassContents.Signature<Self.IdentityType>
```

## Discussion

Discussion Properties: data: Data to be signed with the specified identity authentication: User authentication request to perform identity signature with note: See Error type defined below