# Release History
source: https://developer.mastercard.com/mastercard-processing-authentication/documentation/release-history/index.md

This section provides a history of updates implemented in the Mastercard Processing Authentication API. To stay informed on the latest updates, make sure to visit this page regularly.

The following are the updates, listed in reverse chronological order:

| **Open API Spec Version** | **Release Date**  |                                                                                                                                                                                                                                                                                                                      **Description**                                                                                                                                                                                                                                                                                                                       |
|---------------------------|-------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| v1.1.1                    | 03 November 2025  | • Introduced two new fields `clientEnrolledEmail` and `clientEnrolledMobileNumber` in the `acsAReq` and `acsNewOtp` outbound calls to issuers • Updated the [OpenAPI Specification](https://developer.mastercard.com/mastercard-processing-authentication/documentation/api-reference/index.md) for the `acsAReq` outbound call by making the `transactionDetails.threeDsRequestorAuthenticationType` field optional. The field does not propagate in case the issuer handles 3RI (Merchant-Initiated Authentication) decision-making at their end.                                                                                                        |
| v1.1.0                    | 12 September 2025 | • Introduced a new [MTF environment](https://developer.mastercard.com/mastercard-processing-authentication/documentation/api-basics/index.md#environments) to conduct full User Acceptance Tests (UATs) • Added HTTP status response code to the [Mastercard Processing Authentication error codes](https://developer.mastercard.com/mastercard-processing-authentication/documentation/code-and-formats/index.md#mastercard-processing-error-codes) [oas_authentication_issuer_outbound_v1.1.0.yaml](https://static.developer.mastercard.com/content/mastercard-processing-authentication/uploads/oas_authentication_issuer_outbound_v1.1.0.yaml) (112KB) |
| v1.0.0                    | 30 May 2025       | Initial release of the Mastercard Processing Authentication API on Mastercard Developers [oas_authentication_issuer_inbound_v1.0.0.yaml](https://static.developer.mastercard.com/content/mastercard-processing-authentication/uploads/oas_authentication_issuer_inbound_v1.0.0.yaml) (8KB)                                                                                                                                                                                                                                                                                                                                                                 |

Refer to the [Use Cases](https://developer.mastercard.com/mastercard-processing-authentication/documentation/use-cases/index.md) section for functional explanation and the [API Reference](https://developer.mastercard.com/mastercard-processing-authentication/documentation/api-reference/index.md) section for technical details.