Some forms in Altinn must be signed. Signing is done electronically. This is instead of physical signing.
After you have completed a form and indicated who is to sign, click the 'Send for signing' button. The person or people who must sign the form will then be sent a signature notification via their 'Inbox' in Altinn.
The form can be signed by opening the signature notification and clicking the 'Sign and submit' button. The notification will be sent to the relevant authority when everyone has signed.