David Bisland Duval

David Bisland Duval lived with uncommon enthusiasm, virtue, and generosity. A father, businessman, entrepreneur, pilot, and oarsman, Dave brought energy and wisdom to every part of his remarkable life.

Dave passed away suddenly on July 3, 2026, the eve of America's 250th birthday celebration. He was 86 years old.

Born in Bronxville, New York, on August 30, 1939, Dave always said he was “born two days before Hitler marched into Poland, and grew up during the magical post-war years.” His favorite childhood experiences were family summers in the Adirondacks and summer camp in New Hampshire. He attended Phillips Exeter Academy and Princeton University, where he rowed crew and developed lifelong interests in history and politics. Dave began his career on Wall Street, spending eight years on the trading floor of the New York Stock Exchange.

Seeking adventure and life in the mountains, Dave moved west to Crested Butte, Colorado, in 1969. He entered real estate and entrepreneurship, eventually co-founding Ptarmigan Associates. The firm developed and brokered properties throughout the Gunnison Valley. He later moved to Denver, where he worked in commercial real estate development and became a Colorado partner of the Linpro Company before founding his own development company. His next business venture lasted for decades. Based in Del Mar, California, Dave founded Claiborne Advisors, Inc., and worked as an investment banker, advising on mergers and acquisitions. In the business community, Dave stood out for his classic NY business attire: dress shirt and slacks, 3-button jacket, and his signature pocket square. He was known as “the best-dressed man.”

Throughout his career, Dave was respected for his intellect, preparation, honesty, and judgment. Those who worked with him trusted his counsel because they knew he valued integrity above all else.

Dave was a connector of people and an avid mentor. He was actively engaged in the Chairmen’s RoundTable and other organizations, enriching Southern California’s business community. Whether on Wall Street, in the mountains of Colorado, in an airplane cockpit, at a business meeting, or gathered with friends over a craft beer, he was focused on others, not himself. He devoted his time and talent to helping others succeed. Dave was the man working behind the scenes, without need for recognition.

Dave was a talented athlete, always pushing his limits. His running career drew him to Denver’s early running scene. Year-round, any distance, any weather: sunshine, rain, sleet, and snow, and always in shorts. Running in the Colorado Rocky Mountains was Dave’s passion. He excelled running uphill, his strong legs easily leaving everyone in his trail. Those same mountains are where Dave lured two of his kids, in their pre-teens, up and over Conundrum Pass outside Aspen. He told them there was a McDonald’s at the top of the mountain, promising them a hamburger, French fries, and a milkshake. It worked!

Rowing was a lifelong sport for Dave. He helped start the Rocky Mountain Rowing Club and could often be seen at dawn in his single shell on Lake Dillon, Frisco, Colorado. Later, after relocating to San Diego, he became a member of the San Diego Rowing Club where he competed on the men’s masters rowing team.

It was on the waters of Mission Bay where Dave met Annie Lewis Kostrubala. Each of them rowing and competing for different clubs, their paths soon crossed. It was a perfect match, sparking a relationship of 37 years. Dave referred to Annie as “the absolute love of my life” and credited her with showing him how to love and be loved. Matched in energy, generosity, commitment to others, and a love for the outdoors, “D ’n A” were a dynamic duo. One of their greatest adventures was their epic marriage ceremony and celebration in Siena, Italy, joined by close family and friends.

Dave’s search for perfection was evident in his decades as a private pilot. He learned to fly at Princeton Airport and earned his pilot’s license in 1968. Aviation was one of the great joys of his life, leading to lasting friendships and memorable journeys throughout the American West. A devoted member of the Quiet Birdmen, Dave gave generously of his time and talents to the QB San Diego Hangar. He helped manage finances, organize events, and support the organization he loved. Friends describe him as someone who stepped forward whenever something needed to be accomplished.

Dave was an American patriot. He committed to the study of history, politics, and philosophy and believed citizenship required participation and thoughtful involvement. He supported organizations dedicated to America’s founding principles, notably The Claremont Institute and The Philadelphia Society.

Dave held strong convictions and was willing to defend them vigorously. He did not avoid disagreement or compromise his views. He sought genuine engagement, not hostility. He valued ideas, lively debate, and the people with whom he debated, often sharing a meal or a beer with the same person whose views he was challenging.

Those who knew Dave will remember the qualities that defined him: his booming hello, firm handshake, infectious smile, intellectual curiosity, and genuine interest in others. He approached every experience with enthusiasm and pursued his values with cheerful, confident action. He planned travels carefully, sought out new discoveries, enjoyed great conversations, and developed a legendary appreciation for craft beer, especially IPAs. For Dave, these pleasures were never just about the activity itself; they were about friendship, exploration, and sharing life with others. He loved road trips, experiencing small towns, and appreciating details of the land. Even into his eighties, Dave continued traveling, flying, learning, debating, and pursuing new adventures. He was more full of life and joy than most men a fraction of his age. Dave demonstrated to the world that age should never limit curiosity, growth, or enthusiasm.

Dave was preceded in death by his parents, Gordon and Carolyn Duval; his younger sister, Carol Duval; and his first two wives, Vicki Belding and Jeanne Rose. He is survived by his wife, Annie Lewis Duval; children, Serena (Russ) Vogel, Christopher (Griselle) Duval, Bradford Duval, and granddaughter Maura (JT Roach) Duval; and Annie’s progeny Giovanna (Tom) Meek and grandchildren Tong and Moira; Tadz (Mattie Allen) Kostrubala and granddaughter Maizie Blue; Annika Kostrubala, Christine (Jonathan) Lemon, Alexandra Kostrubala, and many grandchildren. Dave deeply loved his children and grandchildren and treasured time and conversation with them.

Dave requested no formal services, preferring instead a gathering where conversation, community, and friendship come together in a way he cherished. A Celebration of Life will be held later this year. Memorial contributions may be made to The Claremont Institute or the Goodfellow Historical Foundation.

Dave Duval leaves a legacy far greater than professional accomplishment. It lives in the family he loved, friends he inspired, organizations he served, and countless people whose lives were enriched by knowing him. His handshake, his laugh, his strong opinions, and his unmistakable enthusiasm will be deeply missed. Dave embraced life with exuberance. A life like Dave’s is not measured by fame, fortune, or length. It is measured by the people it touches. By that measure, David Bisland Duval lived an extraordinary life.