Guy Spier, a dedicated value investor, has re-evaluated his views on wealth and time after being diagnosed with glioblastoma, pondering what truly constitutes a lasting legacy.

Following the closure of his Aquamarine Fund, Spier has shifted his focus to philanthropy, actively advocating for the development of innovative treatments for glioblastoma, a rare and highly aggressive form of brain cancer.

Spier now considers each day a gift and hopes to leverage his personal experience to raise awareness for rare diseases and attract more capital into related scientific research.

The prominent value investor Guy Spier first gained significant public attention in 2007 when he and a partner spent over $650,000 in a charity auction to win a lunch with the "Oracle of Omaha," Warren Buffett.

Spier, who regards Buffett as his idol, founded the Aquamarine Fund in Zurich, Switzerland, in 1997. Emulating Buffett's investment philosophy centered on compound growth, he initially aimed to build an enduring, albeit smaller-scale, investment empire with the fund.

This value investing strategy proved highly successful over the following years: from 1997 to 2025, the Aquamarine Fund's overall returns outperformed the S&P 500 index, a widely recognized benchmark for fund performance. A pivotal turn occurred in November 2024 when Spier suffered a sudden medical emergency while returning from a family ski trip, a brush with mortality that completely reshaped his definition of life's value.

In an interview for the CNBC Health podcast "On the Road with Becky Quick," recorded at the Berkshire Hathaway Annual Shareholders Meeting, Spier recalled: "It was a freezing cold day in November. Driving back to Zurich, I had a full-body seizure. I was sitting next to my wife, and she was completely beside herself."

He was subsequently airlifted to a hospital for an MRI scan.

"I woke up the next day diagnosed with a brain tumor, and from that moment, my life was completely turned upside down."

The diagnosis was a grade IV glioblastoma: a highly malignant and rapidly growing brain tumor. This is a rare disease, affecting about 4 in 100,000 people. There is currently no cure, with a median survival of just 15 months post-diagnosis and a five-year survival rate below 7%. Treatment outcomes have seen little improvement in recent decades.

In the year following his diagnosis, Spier underwent multiple craniotomies to remove the tumor. However, after the second surgery, the cancer recurred, leading him to realize that standard medical interventions could not control the disease.

"The cancer cells are like seeds in the soil or mold spreading everywhere; you can't cut it all out. Even if you remove all the visible tumor, microscopic cancer cells remain."

Winding Down a Profitable Fund

The life-altering event prompted Spier to reassess his priorities, leaving him unable to continue managing the Aquamarine Fund. Earlier this year, he returned all capital to his investors. In his annual letter, he emotionally explained the decision to wind down the fund, acknowledging it was an agonizing choice.

"Writing that letter to wind down the fund was one of the hardest things I've ever done. It felt like a life plan had been completely derailed, a tragedy in a sense."

Yet, Spier also admitted the closure brought a sense of liberation, allowing him to prioritize time with loved ones over wealth accumulation and to learn to savor life more fully.

"We don't have an infinite amount of time. Death comes for us all. Everyone's time runs out."

Spier prefers not to frame his remaining life as a grim battle against cancer but rather as a game against death: each day lived is a chip earned, and his goal is to accumulate as many days as possible to enjoy life.

Contrasting his current relatively good health against the 15-month median survival statistic, he reflects: "Every day is a gift and should be celebrated. I now fly NetJets, choose business or first class, and last night I opened a very expensive bottle of wine."

However, he remains deeply saddened by the prospect of likely missing future life milestones: "The regret is probably not seeing my grandchildren, my kids getting married, my children graduating from university. When those things are taken away, wealth becomes completely meaningless."

Looking back, Spier often regrets spending half his life focused on making money in the stock market instead of engaging sooner in work with greater social value: "Countless researchers dedicate their lives to developing things that improve life for all of humanity. I have regrets about that."

Nevertheless, with substantial personal wealth, he has found a way to contribute: using his resources to help other glioblastoma patients.

Patients with glioblastoma face an extreme predicament: traditional radiation, chemotherapy, and surgery rarely offer a cure. Forgoing standard treatment drastically shortens life expectancy, yet enduring treatment involves immense physical and mental suffering. The industry desperately needs breakthrough new drugs.

Spier uses an analogy to describe the research challenge for this disease: a bathtub drainage problem. While many new patients are diagnosed each year, they pass away so quickly that a large, stable patient population never accumulates. Without a sufficient patient base, large pharmaceutical companies lack commercial incentive to invest heavily in new drug development; the bathtub never fills up.

"Patients are constantly being added, but they're also constantly dying, making it hard to build a large patient community. Drug companies naturally lack the motivation to invest in R&D."

Advocating for Rare Disease Awareness and Funding Research

Spier is determined to use his industry influence to raise awareness about glioblastoma and accelerate the development of new treatment options.

"I plan to put some of my own savings into research. I'm happy to fund the science."

This is now the core message he wants to convey: leveraging personal influence to increase visibility for rare diseases.

"There are huge gaps in treatment and research for many rare diseases, often just waiting for more attention. My future investments won't be for profit but to advance medical science."

Although his earlier dream of building a century-old asset management firm has been set aside, the resources and experience cultivated over decades in the capital markets are now being channeled to create value in a different way: helping thousands of desperate patients and their families find hope for treatment.

This new form of legacy is one worthy of remembrance, and for the remainder of his life, he will continue striving to create lasting value for future generations.