Subscription removed by Web

[pminf]

Our client reports that some of their contacts don't get an subscripted newsletter.  Related group contacts were "Removed (by Web)" (status in civicrm contact group tab). What does this mean? The contacts affirm, that they don't unsubscribe from the newsletter by themselve.

How can subscriptions be removed by method "Web"? And is it possible to get a list of contacts, whose group contacts are "Removed (by Web)" (via CiviCRM or MySQL-SELECT)?

[pminf]

We found out, that the contacts accidentally unsubscribed themselves using a profile (event registration), which includes the related group checkboxes: During the registration process the contacts were detected as duplicates and as a result their details were overwritten. Because they did not checked any newsletter group checkbox, their existing subscription has been removed (by Web).

So I could answer my first question by my self: How can subscriptions be removed by method "Web"?

#1: via Profile

Are there any other?

I also get a list of apparent accidentally unsubscribed group contacts:

Code: [Select]

SELECT * FROM civicrm_subscription_history WHERE method = 'Web' AND `status` = 'removed'