Google's John Mueller said on Twitter that Google is able to read unsupported structured data, structured data that is in the schema.org docs but is not listed by Google as something they support on the Google developers site. But I would not expect you to see rich results from any of those unsupported structured data schema elements.
John wrote when he was asked if Google sees or "reads" the unsupported structured data on a page, "Yeah, it's on the page with the rest, it's kinda hard not to see it."
Here are those tweets:
Yeah, it's on the page with the rest, it's kinda hard not to see it :). I think it's more of a simplification, as in whether or not Google search gets value out of (or reads value from, essentially) the "unsupported" types.
— 🍌 John 🍌 (@JohnMu) December 5, 2020
Now, the confusion came from a video that was reported on where it was interpreted that Google simply may not read the structured data at all, ignore it completely. John said it was "more of a simplification, as in whether or not Google search gets value out of (or reads value from, essentially) the "unsupported" types."
John explained that there "is a lot of "extra" SD is super obvious," he added "it can be helpful, but it's also limited in the extra value it provides."
Can it be used for ranking? Google has said countless times that structured data is not a ranking factor but John added "how do you rank something purely from SD hints? It's an extremely light signal. If you're worried, make the content more obvious." I suspect the content within the structured data is the ranking signal, not the structured data itself?
In terms of can Google use this structured data that it does not support for rich results? Nope, not unless it is testing new schema support.
What about the non-RR SD that's not absolutely clear from the page? It can be helpful, but it's also limited in the extra value it provides. How do you rank something purely from SD hints? It's an extremely light signal. If you're worried, make the content more obvious.
— 🍌 John 🍌 (@JohnMu) December 5, 2020
The thread goes on and you can check it out over here.
Forum discussion at Twitter.
