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

This section provides a history of updates implemented in the Mastercard Processing Dispute 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  | The `addAttachmentToDisputeCase` API now enforces stricter validation rules for `file.name` based on the [OpenAPI Specification](https://developer.mastercard.com/mastercard-processing-dispute/documentation/api-reference/index.md) pattern: `^[a-zA-Z0-9 _\-\(\)\[\]\$\!\~]{1,64}\.[a-zA-Z]{3,4}$`                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| v1.1.0                    | 12 September 2025 | • Introduced a new [MTF environment](https://developer.mastercard.com/mastercard-processing-dispute/documentation/api-basics-section/environments/index.md) to conduct full User Acceptance Tests (UATs) • Added Idempotency for `POST` methods • Introduced a new `getContractDisputeCases` API `/contracts/{contract_id}/cases` endpoint to fetch all dispute cases created for a specified contract • Added HTTP status response codes to the [Mastercard Processing Dispute error codes](https://developer.mastercard.com/mastercard-processing-dispute/documentation/code-and-formats/index.md#mastercard-processing-error-codes) • Improved the [OpenAPI Specification](https://developer.mastercard.com/mastercard-processing-dispute/documentation/api-reference/index.md) for the `addAttachmentToDisputeCase` API by providing clearer guidance on supported file extensions and maximum file size limitations and correct example value [oas_dispute_v1.1.0.yaml](https://static.developer.mastercard.com/content/mastercard-processing-dispute/uploads/oas_dispute_v1.1.0.yaml) (60KB) |
| v1.0.0                    | 2 July 2024       | Initial release of the Mastercard Processing Dispute API on Mastercard Developers [oas_dispute_v1.0.0.yaml](https://static.developer.mastercard.com/content/mastercard-processing-dispute/uploads/oas_dispute_v1.0.0.yaml) (49KB)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |

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