In 2005, Google introduced the nofollow link attribute as a way for publishers to fight link and comment spam. It also became one of Google’s preferred methods for flagging advertising-related or sponsored links.
On September 10, the company announced two additional link attributes:
- rel=“sponsored” used to relate links as part of advertisements, sponsorships, or other compensation agreements;
- rel=“ugc” used to identify links within user-generated content, such as comments and forum posts.
However, rel=“nofollow” attribute stays valid and publishers don’t have to change existing links. You can use this attribute if you want to link a page but don’t want to imply any type of endorsement or ranking credit. From March 2020, Google will treat this attribute as a hint for crawling and indexing purposes and as a way to better understand how to analyze and use links within their systems.
Google recommends to use “sponsored” and “nofollow” rather than “ugc” for flagging sponsored links in order to avoid possible link scheme penalties. Though the “sponsored” attribute is preferable for such purposes, the decision on what attribute to use is up to a publisher.
You can also use these attributes in combination with each other. For example, rel=“nofollow sponsored ugc” or rel=“ugc sponsored” will hint to Google that such link is sponsored and it comes from user-generated content.