query: SELECT DISTINCT ?item ?office ?person 
  WITH {
    SELECT DISTINCT ?item ?office 
    WHERE {     
      ?office wdt:P1001 ?item ; wdt:P279* wd:Q2285706 .
    }
  } AS %hog_offices
  WHERE {     
    INCLUDE %hog_offices .
    ?person wdt:P31 wd:Q5; p:P39 ?ps .
    ?ps ps:P39 ?office ; pq:P580 [] .
    ?item wdt:P31 wd:Q3624078 . 
    FILTER NOT EXISTS { ?ps pq:P582 [] }
  }