Google Refreshes Rel=Canonical Documentation


Google recently updated its rel canonical documentation to provide clarity on how it handles the extraction of rel canonical annotations. The clarification is not indicative of a change in Google’s approach to rel=canonical annotations but rather aims to explicitly outline the processing methods.

The canonical link relation, as defined in RFC 5988, has always served as the standard Google follows for interpreting rel=canonical annotations. This RFC, established by the Internet Engineering Task Force (IETF), outlines specifications for various Internet and networking technologies, including standards related to HTML rel link attributes.

According to RFC 6596, the rel link attribute specifies when another document is duplicative and designates the preferred original. These parameters have guided Google’s processing of canonical link elements.

The recent changes to Google’s Search Central Documentation primarily focus on rel=”canonical” link annotations that extend beyond specifying duplicative documents, along with some minor revisions to the page.

One notable change is the addition of the word “explicit” to the statement: “Google supports explicit rel canonical link annotations as described in RFC 6596.” This addition emphasizes Google’s adherence to the standards outlined in RFC 6596.

Additionally, a new paragraph has been added to the documentation, clarifying that rel=”canonical” annotations suggesting alternate versions of a page are disregarded. Specifically, rel=”canonical” annotations with hreflang, lang, media, and type attributes are not used for canonicalization. Instead, Google recommends using appropriate link annotations, such as rel=”alternate” hreflang, to specify alternate versions of a page.

In essence, these updates underscore Google’s commitment to following established standards and provide clarity on the appropriate use of rel canonical annotations for canonicalization purposes.