Read Only Access - Personal Network Storage

Hi,

I'm aware that the Forcepoint Web Gateway can enable read-only access to selected Social Media services.

I'm wondering if anyone has managed to apply an equivalent control to services in the Personal Network Storage category?

The specific scenario I have is that an accounting website have chosen to use Slideshare embedded in their site to share a presentation.  This is cateogorised as Personal Network Storage - which our company blocks due to risk to corporate information.

What I'd like to do is allow staff view / read only access to the service so they can consume information - but not open access to the service or category in a manner that allows them to upload information.

Is this possible?

Thanks,

Geoff