Film licensing
If a society wishes to show a film to only members, there is no external advertising beyond your society and there is no charge to members, a film license is not required.
If your society shows a film and wants to charge or ticket the event, raise money for charity and advertise to the wider student body (members and non-members) a film license is required
The best way to purchase a license is to buy the film through the Guild's licensing account, which you will have to pay for out of your society's budget.
Licenses to show films are obtained from the UK distributor (or filmmaker or producer, if no UK distributor).