About: http://webisa.webdatacommons.org/137034396

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	An ECN also is an ATS, or alternative trading system, but is distinguished from a dark ATS by its display of quotes.
http://www.w3.org/ns/prov#wasQuotedFrom	sec.gov