what is the {start time} for {Boston Globe} has {owned by} as {John W. Henry} ?
On what date did John W. Henry become the owner of Boston Globe?
When did John W. Henry become the owner of Boston Globe?
SELECT ?t WHERE { ?g property:owned_by resource:John_W._Henry . ?g property:start_time ?t . resource:Boston_Globe property:owned_by ?g }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q824451> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P127> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q1186372> .
?statement <http://www.wikidata.org/entity/P580> ?value. 
} 

SELECT ?value WHERE { wd:Q824451 p:P127 ?s . ?s ps:P127 wd:Q1186372 . ?s pq:P580 ?value}