Question: Stephen Siegel works at the investment firm based in what city?

Context articles: SkyBridge Capital
Maya Capital
Bain Capital
Archview Investment Group LP
CBRE Group
The Blackstone Group
Stephen Siegel
Zachary Karabell
Tobashi scheme
Multilateral trading facility

SkyBridge Capital is a global investment firm based in New York City, United States.
 It is run by chief investment officer Ray Nolte.
 Founder Anthony Scaramucci had co-managed the firm until January 17, 2017, when sale of the firm was announced.
Maya Capital is a specialist real estate and private equity investment firm based in London.
 Founded in 2014, the Pan-European firm's major activities to date have concentrated on investment in UK real estate outside London.
 Their strategy focuses on creating initiatives, such as asset repositioning, financial structuring, property development, and seeking opportunities resulting from special situations.
Bain Capital is a global alternative investment firm based in Boston, Massachusetts.
 It specializes in private equity, venture capital and credit products.
 Bain Capital invests across a range of industry sectors and geographic regions.
 As of June 2014, the firm managed more than $75 billion of investor capital across its various investment platforms.
Archview Investment Group LP is an institutional alternative investment firm based out of Stamford, Connecticut.
 The firm was founded in 2009 by Founding Principals Jeffrey Jacob and John Humphrey.
CBRE Group, Inc. is the largest commercial real estate services and investment firm in the world.
 It is based in Los Angeles, California and operates more than 450 offices worldwide and has clients in more than 100 countries.
The Blackstone Group L.P. is an American multinational private equity, alternative asset management and financial services firm based in New York City.
 As the largest alternative investment firm in the world, Blackstone specializes in private equity, credit and hedge fund investment strategies.
Stephen Barry Siegel (born September 13, 1944) is the Chairman of Global Brokerage at CBRE (NYSE: CBG), the world's largest commercial real estate services company.
Zachary Karabell is Head of Global Strategies at Envestnet, a publicly traded financial services firm where he works with the board and senior management on corporate strategy and with the investment committee on overall investment approaches for the firm.
 He is also President of River Twice Research.
 Previously, he was Executive Vice President, Chief Economist, and Head of Marketing at Fred Alger Management, a New York-based investment firm.
 He was also President of Fred Alger & Company, a broker-dealer; Portfolio Manager of the China-U.S. Growth Fund (CHUSX); and Executive Vice President of Alger’s Spectra Funds, a no-load family of mutual funds that managed the Spectra Green Fund.
 He founded and ran the River Twice Fund from 2011-2013, a $25 million alternative investment fund which used sustainable business as its primary investment theme.
A tobashi scheme is a financial fraud where a client's losses are hidden by an investment firm by shifting them between the portfolios of other (genuine or fake) clients.
 Any real client with portfolio losses can therefore have their accounts flattered by this process.
 This cycling cannot continue indefinitely and so the investment firm itself ends up picking up the cost.
 As it is ultimately expensive there must be a strong incentive for the investment firm to pursue this activity on behalf of their clients.
A multilateral trading facility (MTF) is a European regulatory term for a self-regulated financial trading venue.
 These are alternatives to the traditional stock exchanges where a market is made in securities, typically using electronic systems.
 The operation of a MTF is considered an investment service.
 The concept was introduced within the Markets in Financial Instruments Directive (MiFID), a European Directive designed to harmonise retail investors protection and allow investment firms to provide services throughout the EU.
 Article 4 (15) of MiFID describes MTF as multilateral system, operated by an investment firm or a market operator, which brings together multiple third-party buying and selling interests in financial instruments – in the system and in accordance with non-discretionary rules – in a way that results in a contract.
 The term 'non-discretionary rules' means that the investment firm operating an MTF has no discretion as to how interests may interact.
 Interests are brought together by forming a contract and the execution takes place under the system's rules or by means of the system's protocols or internal operating procedures.