Update an existing list.

Only the fields listed below can be changed; any other field sent in the list object is ignored. name is required on every request, even when it is not changing — omitting it is rejected. Other fields keep their current value when omitted. name cannot contain HTML. sender_url and sender_reminder are optional: when omitted the stored values stay, an empty string clears them, and a non-empty sender_url must be a valid URL (for lists on the email channel). A list's channel cannot be changed after creation.

Sender address and visibility

The postal sender fields (sender_name, sender_addr1, sender_addr2, sender_city, sender_state, sender_zip, sender_country, sender_phone) and private are updatable, as they are on POST /lists, so the fields the v1 list_edit action wrote can all be written here.

The sender address may be updated in part: when a request carries any of the postal sender fields, the address shown in the footer of the list's campaigns is rebuilt from the list's stored values with the submitted values applied over them, so the fields the request leaves out keep their stored value. A field submitted as an empty string is removed from the address.