The financial world lost a pioneering leader this past weekend when Cassandra Seier, head of International Capital Markets at the New York Stock Exchange, died in a bicycle accident while vacationing in the Bahamas.
Seier, 51, passed away on November 22-23, 2025, on Highbourne Cay. The NYSE confirmed her death on November 24, describing it as a sudden and tragic loss. Before joining the NYSE in 2022, she spent over 24 years at Goldman Sachs, rising to Managing Director in futures electronic execution and clearing sales across Singapore, New York, and London.
The accident occurred when Seier reportedly lost control of her bicycle. She is survived by her husband, Thomas Seier, and their young son. NYSE Group has not released additional details about the circumstances, choosing instead to focus on honoring her remarkable career and lasting impact on global finance.
Key Takeaways
- Cassandra Seier died in a biking accident in the Bahamas on November 22-23, 2025
- She served as Head of International Capital Markets at NYSE since 2022
- Seier worked at Goldman Sachs for over 24 years before joining the NYSE
- She was CEO and President of Women in Financial Markets, championing diversity
- A scholarship fund has been established in her memory through WIFM
- The financial community mourns a trailblazer who mentored thousands of women
A Distinguished Career Spanning Three Decades
Seier’s professional journey reflected dedication and expertise in capital markets. At Goldman Sachs, she built a reputation for calm expertise and forward-thinking leadership. Her role involved futures electronic execution and clearing sales, where she managed complex international operations.
After joining the NYSE, she led efforts to attract new listings from companies worldwide. Her work expanded the exchange’s international presence, particularly in emerging markets. Colleagues described her as laser-focused on getting the job done while always making time to mentor the next generation.
Born and raised in Singapore, Seier earned a BA in Finance with a minor in Economics from the University of Oregon. She graduated summa cum laude and became a CFA charterholder in 2004. Her academic achievements laid the foundation for a career marked by continuous advancement and industry recognition.
Champion for Women in Financial Services
Beyond her corporate roles, Seier served as CEO and President of Women in Financial Markets, a nonprofit organization dedicated to connecting and elevating female professionals. Under her leadership, WIFM created opportunities for thousands of women through education, coaching, mentorship, and access to influential networks.
WIFM’s board described her loss as immeasurable. The organization praised her as a shining light and visionary leader who brought unstoppable energy to every initiative. She worked tirelessly to build environments where women felt seen, supported, and empowered to rise.
Her legacy includes programs she championed, the community she nurtured, and countless doors she opened for women following in her footsteps. WIFM has established a scholarship fund in her memory, with contribution details available through the organization’s official channels.
Industry Mourns a Trailblazing Leader
Tributes poured in from across the financial sector following news of Seier’s death. NYSE Group President Lynn Martin called her a colleague and friend who embodied everything that makes the NYSE team great. Martin highlighted her tireless defense of principles and fierce championship of every customer she touched.
Jonathan Epstein, head of International for Continental Exchange in Tel Aviv, remembered Seier as a true trailblazer who left an indelible mark on everyone she encountered. He praised her exceptional guidance in expanding NYSE’s International Capital Markets presence, calling it a testament to her vision and dedication.
Christopher Perkins, president of Coinfund, noted on LinkedIn that Seier was always on top of her game—thoughtful, smart, and a culture carrier. He described how she owned every room and remained on the cutting edge of forward thought.
A Legacy That Will Endure
Seier also served as chairwoman of the World Federation of Exchanges’ listings working group. In this capacity, she helped shape global standards for capital markets and fostered collaboration among international exchanges.
Her recent appearances included WebSummit Lisbon and WIFM’s NYC Gala on October 30, 2025, where she spoke as president and CEO. Photos from these events captured her vibrancy and passion for advancing women in finance.
The financial community has rallied around her family during this difficult time. WIFM created a webpage where friends and colleagues can share memories of Seier. One advisory council member wrote about building WIFM side by side for six years, pushing forward and believing in what they were creating together.
Social media engagement reflected widespread mourning, with NYSE’s tribute posts receiving over 5,000 views and Reuters coverage reaching 17,000-21,000 views within hours. The discourse focused on inspiration rather than speculation, with users sharing her recent accomplishments and thanking her for paving the way.
Her impact on diversity in capital markets will continue through the women she mentored, the programs she built, and the barriers she broke. As WIFM stated, her legacy is woven into every part of the organization and will guide the community for years to come.
