An anonymous group of artists in San Francisco are covertly going into libraries and book stores and covering definitions of "marriage" with stickers featuring an updated definition.

The Oxford American Dictionary defines marriage as, "The formal union of a man and woman, typically recognized by law, by which they become husband and wives."

The video, posted by the group HACKmarriage, begins by showing a few news headlines from the recent Supreme Court rulings on same-sex marriage.

It then shows anonymous people cutting out stickers with the definition of marriage as, "The formal union of two people, by which they become partners for life.

Group members wearing hooded sweaters are then shown going into a San Francisco Public Library, bookstores and a Target seeking out dictionaries where they put the fortune cookie fortune-sized sticker over the old definition.

The group did not immediately respond to request for comment.