Before sending a file, you can decide whether or not to allow your recipients to forward the files you send. This feature is available in the following file formats:
Allow or Restrict Forwarding options are available for Team and Enterprise plans.
How to Allow or Restrict Forwarding
Go to the Send Files section
Select a file to share.
In Access, select Only people I specify.
Decide whether you want to allow or restrict forwarding. As default, Restrict forwarding is automatically ticked. Uncheck the box to allow forwarding.
4. Key in email address of your recipients.
5. Continue selecting your other preferred security settings and click Send when ready.