I've been working on marking up website's HTML with Microdata. There are Product, WebPage, WebSite, Organization and other elements. Eventually I managed to nest everything under one element, which is<body itemscope itemtype=WebPageThe hierarchy isWebPage  itemprop isPartOf WebSite     itemprop SearchActionitemprop breadcrumbitemprop mainContentOfPage WebPageElement  itemprop // Products, ItemList, etc. (depends on the page)itemprop copyrightHolder Organization  itemprop name  ...There are actually more elements, but what I want to ask is:Will search engines process nested elements like Organization fully, as if it were found separately like this:WebPageOrganizationI'm concerned that search engines may treat copyrightHolder Organization only as a property of WebPage and not as a full, standalone entity (worthy of showing up in search engine results on its own, like company information summaries show up on the side of search results).
Do search engines process nested Microdata objects?
seo;microdata;schema.org
If a search engine supports a specific Schema.org type (like Organization) and also supports a specific property that takes another item as value (like parentOrganization), it would of course parse this nested item, otherwise you couldnt really speak of support.So the question really should be: Which Schema.org types/properties does make the search engine use of, and in which context?For example, it could be conceivable that a search engine considers only a top-level Organization item for doing something (e.g., displaying a rich snippet), but not a nested Organization item. This would be stupid, but that doesnt mean it couldnt happen. Every search engine (and other consumer) has its own rules and quirks. Unless you know about them specifically (in which case you could adapt, if your care about that consumer), you should stick to the official definitions and documentation on http://schema.org/, and you should not limit the expressiveness of your structured data just because there could exist consumers that cant handle it.About your example:I'm concerned that search engines may treat copyrightHolder Organization only as a property of WebPage and not as a full, standalone entity (worthy of showing up in search engine results on its own, like company information summaries show up on the side of search results).Well, it is only a property of the WebPage. Without denoting anything in addition, a consumer only learns that this Organization is the copyright holder of the web page. I wouldnt expect a search engine to do anything fancy with this (except, of course, displaying whos the copyright holder).If you have a page about a Thing and an Organization holds the copyright for this page, the interesting part for displaying rich snippets in general-purpose search engines would typically be the Thing, not the Organization.If you want to denote that the page represents the Organization, you could use the mainEntity property. Using this could make sense on the homepage and the about page of the organizations official website.By the way, this mainEntity property is what you probably want to use instead of mainContentOfPage in your example (background).