In 2019, Google transitioned `rel=nofollow` from a strict directive to a ranking "hint." Understanding the value of UGC and Sponsored tags ensures compliant, high-ranking backlink equity.
1. HTML Link Attributes & Google Treatment
- `rel="dofollow"` (Standard Link): Passes full PageRank authority and topical relevance.
- `rel="nofollow"`: Treated as a hint for indexing and crawl discovery; contributes to profile naturalness.
- `rel="sponsored"`: Required for paid advertorials, affiliate links, and sponsored content under Google Webmaster Guidelines.
- `rel="ugc"`: Recommended for user-generated content, forum posts, and blog comments to prevent spam liability.