How long is the 'Loose Check' cookie stored for?

Just wondering if there is an expiry on this 'Loose Check' cookie option, that prevents multiple form submissions. Ideally we don't want to appear to hold any users data for too long, so I'm hoping it has an expiry after a set amount of days. 

Please note that if you enable Loose Check in form, it will add a cookie in browser after form is submitted. It will only be cleared after user clear browser cache and cookies. 

Unfortunately it is not possible to set expiry date of cookies.