James Koessler

JAMES KOESSLER is an equity capital markets and public company lawyer with 11 years of experience on UK, European, and transatlantic transactions. He acts for companies, banks, and investors on IPOs, secondary raises, demergers, and spin-offs, from listing readiness onwards, and for major shareholders, including private equity and sovereign investors, on sell-downs, stake management, private investments in public equity (PIPEs), and cornerstone investments. He also acts for banks as sponsor under the UK Listing Rules and in connection with their underwriting roles.

“James is an incredibly well-rounded practitioner. He is very good with clients and works incredibly well under all sorts of pressure.”
Chambers UK 2025

James is ranked in Chambers UK (2025–2026), Chambers Europe (2026), and Chambers Global (2026) for Capital Markets: Equity. He was named a “Rising Star (Global)” at the IFLR Europe Awards 2025 and selected as a “Rising Star” by Financial News (Dow Jones) in 2026.

• Metlen Energy & Metals on its primary listing in London and secondary listing in Athens, the first euro-denominated listing in the FTSE 100 and London's largest primary listing of 2025 by market value.
• Pfizer on:

o   The demerger and listing of Haleon in London and New York, the largest London listing since Glencore
      in 2011 and one of Europe's largest ever demergers.
o   Its four sell-downs of its stake in Haleon, totaling US$13.4 billion.

• The underwriters on the IPO and Bucharest listing of Hidroelectrica, the largest IPO in Europe in 2023 (IFR Sustainable Equity Issue of the Year 2023).
• The banks on Compass Group's £2 billion cashbox placing, the first accelerated placing by a FTSE 100 company to include a retail offer.
• Allegro.eu on its IPO in Warsaw, the largest IPO in Warsaw Stock Exchange history (IFR EMEA IPO of the Year 2020), and on its €881 million acquisition of Mall Group and WE|DO, partly paid in new shares.
• Jackpotjoy (later Gamesys Group) on its:

• The Hellenic Financial Stability Fund on its €690.6 million sale of a 10% stake in National Bank of Greece, the final step in Greece's post-crisis bank privatizations.
• The underwriters on InPost's IPO and listing on Euronext Amsterdam, the largest IPO in Europe in 2021.
• EDP on its €1.02 billion rights issue to fund its acquisition of Viesgo.
• The banks on accelerated bookbuilds, including Wendel's €750 million sale of a 6.7% stake in Bureau Veritas and Sacyr's €222 million capital increase.
• One of Videndum's lenders on the company's 2026 refinancing, including its £85 million equity raise and the exchange of part of the lender's debt for new shares.
• Morgan as sponsor on Petrofac's proposed 2025 balance sheet restructuring and placing, including its FCA-approved prospectus; the restructuring did not complete.
• The underwriters on the IPO and London premium listing of Bridgepoint, the first major listing by a UK private equity firm in almost 30 years.
• The underwriters on the IPO and London premium listing of Network International.
• Clayton, Dubilier & Rice on its investment in SIG alongside SIG's £165 million equity raise.
• A sovereign wealth fund on its PIPE investment in a UK listed company and on cornerstone investments in two IPOs in the Gulf.
• The Generation Essentials Group on its London secondary listing alongside its New York Stock Exchange listing.
• Huatai Securities on its London GDR listing, the first listing on the Shanghai-London Stock Connect (IFLR Europe Equity Deal of the Year 2020).
• Volvo Cars on the distribution of 62.7% of its Polestar shareholding to its shareholders.
• Specialist Fund Segment-listed EJF Investments on multiple issues of zero dividend preference (ZDP) shares and rollover offers.
• OMV Petrom on the cancellation of its London GDR program and delisting from the London Stock Exchange.

The above matters were handled prior to joining Sidley.

• AI Strategy for Legal Leaders, Stanford Law School, 2026