You apply for funding with a film fund (many film funds around the world require an ISAN)
Your film or television programme crosses borders: festival screenings, distribution abroad, a requirement at iTunes Switzerland, for example
You claim your statutory copyright remuneration, such as private copying levies (in some countries an ISAN is required by law for this)
You want to keep control of the credits and metadata attached to your film
You want the use of your work to be traceable through the distribution chain (accuracy and cost savings)
You want to prevent misuse of your work
You value a modern distribution system
You can use the number in these ways:
As a 24-character code Use the number in contracts, on credit lists, in print and on packaging. An ISAN looks like this: 0000-0001-ED3A-000B-5-0000-0000-M
In your database Record it in your own database and use it in communication with distributors, agents, collecting societies and others. At iTunes and Google Play, for example, you can enter an ISAN as a field.
As a barcode Put it on packaging and labels as a two-dimensional Data Matrix barcode, which makes tracking goods easier and protects against piracy.
Embedded in the work Use the code as a digital audio or video fingerprint or watermark, which makes rights management easier.