Uploading images for distinct clients

We use Cognos 10.1.1 in a SaaS environment with multiple clients accessing the system. We have a requirement where clients want to use logos on reports created in Business Insight Advanced and in Report Studio. The catch is that each client needs to be able to retrieve their logo but not see other client logo or images. The client does not need to be able to upload the image…just reference the folder where they exist. Are there any ways to secure folders so that only users from a specific client can access a given folder?