Research by Polina Efremenko

ESG and Bond Market Resilience: Evidence from the COVID Crisis

With Sudheer Chava and Carolina Salva, Journal of Banking & Finance, 2026

• We document a smaller expansion of the negative CDS-bond basis and lower selling pressure during the Covid crisis for bonds issued by firms with high environmental and social (E&S) scores, relative to bonds from low E&S firms. This pattern is consistent with lower investor outflows from sustainability focused funds rather than fund managers discriminating among which bonds to sell. Our results suggest that the relative performance of high and low E&S bonds during a crisis is influenced not only by shifts in firm fundamentals, but also by non-fundamental factors such as investor preferences and trading behaviour.
• Presentations: EFMA 2024 (University of Lisbon - ISEG), CSR, the Economy and Financial Markets Conference 2023 (WHU-Otto Beisheim School of Management), SESTEF 2023 (University of Southampton), SFI Research Days 2023 (Study Center Gerzensee), World Finance Conference 2022 (University of Turin)

Read the published article · DOI: 10.1016/j.jbankfin.2026.107634

@article{chava2026esg,
  title   = {ESG and bond market resilience: Evidence from the Covid crisis},
  author  = {Chava, Sudheer and Efremenko, Polina and Salva, Carolina},
  journal = {Journal of Banking \& Finance},
  volume  = {185},
  pages   = {107634},
  year    = {2026},
  doi     = {10.1016/j.jbankfin.2026.107634}
}

The Impact of Western Sustainability Regulations on the Global South

With Peter Fiechter, Florian Habermann, Gaia Melloni, Nicolas Rudolf, and Sandra Schafhäutle

• The project focuses on the EU Deforestation Regulation (EUDR) and its spillover effects on producers and supply chains in exporting countries.
• Funded by the Swiss National Science Foundation (SNSF), project funding grant no. 10006182 (2026–2029)

Green Equity Classifications: Evidence from the London Stock Exchange's Green Economy Mark

Solo-authored

• The World Federation of Exchanges urges stock exchanges to adopt green equity labels to reduce information gaps about firms' environmental performance and attract sustainability-oriented investors. I test whether these benefits materialize by studying the London Stock Exchange's Green Economy Mark (GEM), awarded to listed firms generating over 50% of revenues from environmentally positive products and services. I find an initial positive stock-price reaction to GEM announcements, but it quickly reverses, producing no overall abnormal returns. The GEM provides no incremental information and does not increase demand from either existing or new investors, suggesting limited information-processing benefits. The initial response appears to reflect temporary sentiment that fades as markets reassess the GEM's value, implying exchanges should reconsider green stock-labelling criteria.
• Presentations: EAA Talent Workshop 2024 (IE University), ICFAB 2024 (University of Southampton)

Read on SSRN · DOI: 10.2139/ssrn.5162607

@misc{efremenko2025green,
  title  = {Green Equity Classifications: Evidence from the London Stock Exchange's Green Economy Mark},
  author = {Efremenko, Polina},
  year   = {2025},
  note   = {SSRN Working Paper},
  doi    = {10.2139/ssrn.5162607}
}