Facebook announced it will alter the Beacon feature of its newly launched ad-platform after more then 50,000 users haves signed a petition initiated by the advocacy group Moveon.com.

Beacon is an advertising platform that tracks Facebook’s member transactions on third-party partner sites and transforms them into product/service endorsements. The endorsements are then inserted to their friends’ “news feeds.”

Of course Facebook members were automatically opted-in to the program and they are able to opt out but only on case-by-case basis. That means that for example you must opt-out for each of the 44 participants, but take a minute to imagine how much time you’ll spend opting-out for, let’s say, 200 sites.

MoveOn.com and other users said that Facebook’s Beacon is “a huge invasion of privacy”. Also, some of the Facebook’s members were outraged after their surprise gifts were unveiled to their loved ones.

As a consequence, Facebook announced in a statement posted on its website that made it some changes to Beacon.

“Users must click on “OK” in a new initial notification on their Facebook home page before the first Beacon story is published to their friends from each participating site. We recognize that users need to clearly understand Beacon before they first have a story published, and we will continue to refine this approach to give users choice.” the statement reads.

Also, Facebook’s Beacon offers now to the users clear options in ongoing notifications to either delete or publish. If they delay in making this decision, the notification will hide and they can make a decision at a later time. The complete list of changes can be read here.

According to various reports, some of the companies that were involved as advertising partners in the new Facebook ad-platform have decided to abandon the service.