Discover Financial Services

Discover ProtectBuy 3-D Secure API

ProtectBuy is Discover Global Network's EMV 3-D Secure (3DS) cardholder authentication service. Built on the EMVCo 3-D Secure protocol, it lets merchants, acquirers, and 3DS servers authenticate Discover, Diners Club, and network-alliance cardholders at checkout, challenge high-risk transactions with a one-time password, and shift liability for card-not-present fraud across web, mobile, and connected-device commerce. Documentation and OpenAPI reference are published in the partner-gated Discover Developer Center; full specs require partner authentication.

GitHub

Documentation

📖
Documentation
https://www.discoverglobalnetwork.com/solutions/fraud-security/protectbuy/

Other Resources

🔗
DeveloperPortal
https://developer.discover.com/
🔗
APIsJSON
https://raw.githubusercontent.com/api-evangelist/discover-financial/refs/heads/main/apis.yml

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API entry from apis.yml

apis.yml Raw ↑ 
aid: discover-financial:protectbuy-3ds
name: Discover ProtectBuy 3-D Secure API
description: ProtectBuy is Discover Global Network's EMV 3-D Secure (3DS) cardholder authentication service.
  Built on the EMVCo 3-D Secure protocol, it lets merchants, acquirers, and 3DS servers authenticate Discover,
  Diners Club, and network-alliance cardholders at checkout, challenge high-risk transactions with a one-time
  password, and shift liability for card-not-present fraud across web, mobile, and connected-device commerce.
  Documentation and OpenAPI reference are published in the partner-gated Discover Developer Center; full
  specs require partner authentication.
humanURL: https://www.discoverglobalnetwork.com/solutions/fraud-security/protectbuy/
tags:
- 3D Secure
- Fraud
- Authentication
- Payments
- United States
tags_raw:
- 3-D Secure
- Fraud
- Authentication
- Payments
- United States
properties:
- type: DeveloperPortal
  url: https://developer.discover.com/
- type: Documentation
  url: https://www.discoverglobalnetwork.com/solutions/fraud-security/protectbuy/