The way that co-sponsors are added to legislation is that...

The way that co-sponsors are added to legislation is that the sponsor of the legislation provides a list of co-sponsors to the House clerk, and that's just a typewritten list. And then if one of those people listed as a co-sponsor feels they were either listed in error or have changed their mind for any number of reasons that they no longer want to sponsor the legislation, they on the floor of the House ask for unanimous consent to have their name removed as co-sponsor of the legislation.