Help:Special property Last editor is

The Last editor is property is a special property in Semantic MediaWiki with a built-in meaning: it holds the page name of the user who created the last page revision. This special property is available since Semantic MediaWiki 1.7.1 and it is possible to control if this special property is used or not. It is disabled by default. See the help page on the configuration setting $smwgPageSpecialProperties for details on configuring SMW for special page related properties including "Last editor is".

This property can be used to refer to page creation dates in inline queries, where it can be used like any other property of datatype "Page". This special property should never be set manually, since SMW will take care of setting its value. Starting with Semantic MediaWiki 2.2.0 it is no longer possible to manually add values for this special property.CiteRef::gh:smw:914

See the property page "Last editor is" to see which pages use this special property on this wiki.