Rosen Dimitrov Kralev

Rosen Dimitrov Kralev is a quantitative trader and IMO gold medalist (Bulgaria, 2003-2005). After a Harvard AB in Mathematics (2009) he spent 2009-2017 in algorithm development at Virtu Financial, a high-frequency market maker (FINRA-confirmed 09/2009-02/2017). He did reinforcement-learning research at Berkeley AI Research (2017-2018, co-author of 'Guided Meta-Policy Search', NeurIPS 2019), was listed in quant research at Ritter Alpha from 2019, and served as Director of Trading at quantitative HFT firm Vatic Labs from 2024 until resigning on 2026-01-07; he sued Vatic in Delaware over an unpaid $1.5M bonus. Current employment as of 2026 is not confirmed.

Notes8

• Quant employment verification: CONFIRMED. Primary sources establish actual quantitative-finance employment, not just index listings. FINRA BrokerCheck (CRD# 5694307) records Rosen Dimitrov Kralev as a registered broker with VIRTU FINANCIAL BD LLC, New York, NY, 09/2009-02/2017 - Virtu is a global high-frequency market maker and electronic liquidity provider. Business Insider (2026-02-06) and a Delaware Superior Court docket (N26C-01-309) report he was hired in 2024 as Director of Trading at Vatic Labs/Vatic Investments, a systematic quantitative high-frequency trading firm, and resigned 2026-01-07 before suing over an unpaid bonus. Index/enrichment (not primary) lists a Ritter Alpha quant-research role from 2019; Business Insider independently corroborates 'prior stints at Virtu Financial and Ritter Alpha'. Employer classification: Virtu Financial = high-frequency trading/market-making; Vatic Labs = systematic quantitative proprietary trading (statistical arbitrage + ML, markets US/intl equities, futures, options); Ritter Alpha LP = SEC-registered investment adviser running systematic quantitative absolute-return strategies. Student programs/competitions (IMO) are excluded as non-employment.
• Hired at Vatic Labs in 2024 as Director of Trading on a $350,000 salary plus a guaranteed $1.5M bonus; received only the first $375,000 installment (Jan 2025), resigned 2026-01-07 and sued Vatic in Delaware Superior Court (N26C-01-309) on 2026-01-15 alleging breach of contract and unjust enrichment - a rare public window into a proprietary quant firm's capital troubles.Feb 6, 2026
• FINRA BrokerCheck is the strongest employment record: Rosen Dimitrov Kralev, CRD# 5694307, 'previously registered' broker with VIRTU FINANCIAL BD LLC (CRD# 148390), New York, NY, from 09/2009 to 02/2017 - a regulated primary-source span for the Virtu role.Feb 2017
• Vatic Labs (Vatic Investments LLC / Vatic Labs Operations LLC) is a Midtown Manhattan quantitative trading firm and electronic liquidity provider building ML-driven 'autonomous trading agents' for US/international equities, single-stock swaps, ETFs, futures and options - confirming the employer genuinely operates in quantitative trading, not merely a name containing 'quant'.
• Index-only claim (LinkedIn enrichment): a 'Quant Research' role at Ritter Alpha from 2019 listed as current. This is NOT independent primary-source confirmation; it conflicts with the confirmed Vatic Director of Trading role (2024-2026) that Business Insider characterizes as following his Ritter Alpha stint. Treat current employment as UNRESOLVED.
• Co-author of 'Guided Meta-Policy Search' (arXiv 1904.00956), a meta-reinforcement-learning paper presented at NeurIPS 2019, with R. Mendonca, A. Gupta, P. Abbeel, S. Levine, C. Finn - placing him in the Berkeley AI Research (Abbeel/Levine) orbit during 2017-2019; the Berkeley RLL people page lists him as a visitor/volunteer.2019
• IMO identity confirmed from official IMO results: Rosen Dimitrov Kralev represented Bulgaria, gold medal 2003 (37 pts), gold 2004 (36 pts), gold 2005 (42/42, rank 1). Olympiad results are competitions, not employment.2005
• Ritter Alpha LP, founded 2019 by Gordon Ritter, is an SEC-registered investment adviser running systematic quantitative absolute-return strategies across multiple asset classes - confirming the employer operates in quantitative finance. Note: the adviser is no longer SEC-registered per IAPD.
• Undergraduate education: Harvard AB in Mathematics (2005-2009) per LinkedIn enrichment (index-only). Harvard math department publication lists 'Rosen Kralev '09' as a Harvard College Mathematics Review copy editor and as a Putnam honorable mention, corroborating the Harvard 2009 mathematics affiliation from independent Harvard sources.
• No dedicated quant-finance role has been confirmed at a bank, asset manager, or energy/crypto trading firm; all confirmed roles are at HFT/proprietary trading firms (Virtu, Vatic) and a systematic asset manager (Ritter Alpha).