Market technology providers routinely push the envelope in the rush to execute trades in the smallest possible fraction of a second. The 800-employee, Sri Lanka–based MillenniumIT, which London Stock Exchange Group acquired in 2009 and has been headed by John Mackay (Mack) Gill since 2013, developed one of the world's fastest exchange platforms for the LSE and has more than 40 client sites around the world using its systems. It ensures extremely low latency by deploying field-programmable gate array (FPGA) hardware in operations such as the LSE Group Ticker Plant.
But high-performance technologies aren't just for the front end of the transaction cycle. With the Millennium PostTrade clearing, settlement, and depository platform, the company relies on graphics processing units (GPUs) to deliver real-time, cross-asset analytic and risk management capabilities. Having completed a sizable installation of PostTrade last year at the Singapore Exchange, MillenniumIT is taking it up a notch with the next-generation platform now in progress for the LSEG-controlled clearinghouse LCH. "Real-time capabilities will be extended to stress testing, backtesting and member-driven 'what if' scenarios, providing a comprehensive and flexible real-time enterprisewide risk management framework," LSEG said in an announcement last fall. "Clearinghouses are systemically important entities that cut across many financial institutions," notes Gill, 47, who spent 19 years with various units of SunGard Data Systems before becoming CEO of MillenniumIT. "Improved analytics in real time, with enhanced margining and netting capabilities, are important tools for central counterparties such as LCH."
 2. Chris Isaacson Bats Global Markets  3. Bradley Peterson Nasdaq  4. Brad Levy MarkitSERV  5. Dan Keegan Citi |
 6. Glenn Lesko Bloomberg Tradebook  7. Bryan Durkin CME Group  8. Mayur Kapani Intercontinental Exchange  9. Mike Blum KCG Holdings  10. Raj Mahajan Goldman Sachs Group |
 11. Ronald DePoalo Fidelity Institutional  12. Nick Themelis MarketAxess Holdings  13. Jenny Knott NEX Optimisation  14. Billy Hult Tradeweb Markets  15. Rob Park IEX Group |
 16. Bill Chow & Richard Leung Hong Kong Exchanges and Clearing  17. John Mackay (Mack) Gill MillenniumIT  18. Paul Hamill Citadel Securities  19. Eric Noll Convergex  20. Veronica Augustsson Cinnober Financial Technology |
 21. Tyler Moeller & Joshua Walsky Broadway Technology  22. Alasdair Haynes Aquis Exchange  23. Gaurav Suri Arcesium  24. Manoj Narang Mana Partners  25. Michael Chin & Neill Penney Thomson Reuters |
 26. Robert Sloan S3 Partners  27. Anton Katz & Stephen Mock AQR Capital Management  28. Donal Byrne Corvil  29. Stu Taylor Algomi  30. Alfred Eskandar Portware |
 31. Steven Randich Financial Industry Regulatory Authority  32. R. Cromwell Coulson OTC Markets Group  33. Peter Maragos Dash Financial  34. John Fawcett Quantopian  35. Donald Ross III PDQ Enterprises |
 36. Jennifer Nayar Vela Trading Technologies  37. Dan Raju Tradier  38. Susan Estes OpenDoor Trading  39. David Mercer LMAX Exchange  40. Oki Matsumoto Monex Group |
