@codeinabox It's different.
Webmention is similar to #pingback that was popular with blogs and websites.
Webmention basically sends information to the sites linked that hey, I mentioned your link in my website.
So, if a third-party site is using OSM (as an example) materials but did not include any link back to them, webmention won't be triggered.
Also, one can trigger webmention without actually having a visible link. So, in this case, providing Attribution, since there is no visible link, there still is no Attribution given.
^_^