You can send your PDF invoices to several e-mail addresses at one time. You simply enter a comma between each e-mail address (no spaces) and the invoice will be delivered to all e-mail addresses.
Example that works: (separated by commas without spaces)
mail1@mail.se,mail2@mail.com,mail3@mail.se
Examples that do not work: (Separated by commas and spaces/semicolon)
mail1@mail.se , mail2@mail.com , mail3@mail.se
mail1@mail.se ; mail2@mail.com ; mail3@mail.se