While Google supports the data-nosnippet HTML attribute, Microsoft Bing does not, clarified Fabrice Canel of Microsoft on Twitter.
The data-nosnippet attribute lets you designate textual parts of an HTML page not to be used as a snippet in the search results in Google, but it does not work for Bing.
Fabrice Canel said “We do not support data-nosnippet tag.”
We do not support data-nosnippet tag.
— Fabrice Canel (@facan) April 5, 2022
For Google, the help document explains that you can designate textual parts of an HTML page not to be used as a snippet. This can be done on an HTML-element level with the data-nosnippet HTML attribute on span, div, and section elements. The data-nosnippet is considered a boolean attribute. As with all boolean attributes, any value specified is ignored. To ensure machine-readability, the HTML section must be valid HTML and all appropriate tags must be closed accordingly. Google typically renders pages in order to index them, however rendering is not guaranteed. Because of this, extraction of data-nosnippet may happen both before and after rendering. To avoid uncertainty from rendering, do not add or remove the data-nosnippet attribute of existing nodes through JavaScript. When adding DOM elements through JavaScript, include the data-nosnippet attribute as necessary when initially adding the element to the page’s DOM. If custom elements are used, wrap or render them with div, span, or section elements if you need to use data-nosnippet.
Again, Microsoft Bing does not listen to this attribute.
Forum discussion at Twitter.