Your MaxMind license key should be treated essentially as a password, so we recommend storing license keys securely in a password manager. Each key is a unique identifier for your account, which, if obtained by an unauthorized individual, may result in misuse of your MaxMind products and services.
When using your license key in your code, make sure you store it securely. Never store your license key where it can be read by other users on shared resources (e.g. version control, code, public HTML, etc.).