Does the link to sign the document expire?

When a SignRequest is sent to a contact, they will receive an email containing a link which will allow them to open the document to sign. 

The signing links in the emails will expire if they are not clicked within 7 days of sending.  However, the document can still be signed.  The signer will be redirected to a page where a new SignRequest email will be sent, which again will be clickable for 7 days.