Cisco Firewall :: ASA 5585 Number Of Licenses Used By Multiple Security Contexts

We are going to deploy a active/active setup of 2 ASA 5585's. Here we will implement a concept of security zones through context's where different services will be firewall through a separate firewall context. will a security context consume 1 or 2 licenses because we are running in a Active/active setup?  Right now I got completely confused when my manager asked me that question.I would say that we only use on security context license - but since we are running in a active/active setup - even though the other instance is standby - will it consume a context license? We are using ASA OS 8.4.x.