Given the input sentence, please extract the subject and object containing a certain relation in the sentence according to the following relation types, in the format of "relation1: word1, word2; relation2: word3, word4". Relations include: product/material produced; manufacturer; distributed by; industry; position held; original broadcaster; owned by; founded by; distribution format; headquarters location; stock exchange; currency; parent organization; chief executive officer; director/manager; owner of; operator; member of; employer; chairperson; platform; subsidiary; legal form; publisher; developer; brand; business division; location of formation; creator.

ENLARGE U.S. authorities allege Navinder Singh Sarao contributed to the swift drop in stocks on May 6, 2010, known as the “flash crash.” Photo: Lauren Hurley/PA Wire/Zuma Press At a hearing in central London on Friday, District Judge Quentin Purdy agreed to the defense lawyer’s request to adjourn the hearing, setting a new date in February next year, after U.S. prosecutors released evidence overnight alleging that Mr. Sarao started to use illegal trading strategies in January 2009, six months earlier than previously claimed.

Answer: position_held: Quentin Purdy, District Judge