OVERLAND PARK, Kan. – September 3, 2025 – 10:00 AM Eastern Time – Mariner, a national financial services firm, today announced sustained growth for its Mariner Independent platform, a destination for wirehouse advisors seeking autonomy, scale and flexibility. The latest example is the launch of Promontory Wealth by veteran advisors Kyle Briggs, CFA®, and Joseph Thomason, CFA®, who will leverage Mariner’s resources and infrastructure to accelerate their expansion.
The duo, each with more than a decade of experience advising high-net-worth individuals and families, are leaving a traditional wirehouse to establish their own brand and business. Backed by Mariner Independent’s scale, resources, and flexibility, Promontory Wealth will benefit from a platform designed to propel advisor success by combining business infrastructure with strategic development support.
Mariner Independent now oversees approximately $40 billion in assets under advisement, making it a central driver of Mariner’s overall growth strategy. Earlier this summer, the firm named Rob Sandrew head of Mariner Independent, supported by Verne Marble as managing director, to deepen engagement with affiliate advisors and expand resources in practice management, valuation services, estate planning, and tax strategies.
“What Kyle and Joe are doing with Promontory Wealth is a perfect example of why we are investing so heavily in Mariner Independent,” said Sandrew. “Advisors want the freedom to build and own their businesses, but they also want the confidence that comes from having growth expertise behind them — including business owner resources, advanced planning, an open architecture, and tax specialization. Our commitment goes beyond transition support; we’re partnering with Promontory to actively drive their growth, ensuring they have the tools and pathways to expand quickly and sustainably.”
This move reflects a broader industry trend of experienced wirehouse advisors choosing independence to gain greater control over client experience and growth potential. Mariner Independent has become the destination of choice by combining comprehensive planning, investment access, integrated technology, and practice-management support with the freedom to build enduring firms.
“Launching Promontory Wealth allows us to create something truly our own while giving our clients the same depth of resources they would expect from the largest firms,” said Kyle Briggs, co-founder of Promontory Wealth. “After significant due diligence, we selected Mariner Independent as our partner because of their unmatched ability to support advisors transitioning from a wirehouse environment. Mariner gave us something no other firm could: the affirmation that we could build a brand, stay true to our principles, and still have the scale and expertise behind us to chart a clear path for future expansion.”
“Our decision to go independent was about gaining the flexibility to deepen client relationships and build a firm that reflects our values,” said Joe Thomason, co-founder of Promontory Wealth. “With Mariner’s platform, we can focus entirely on clients while positioning our business for long-term growth. We chose Mariner not just for independence, but for their proven ability to help firms expand — whether through scaling relationships, adding new services, or pursuing acquisitions. With Mariner, we know this is just the beginning.”
Promontory Wealth will serve clients across the greater Los Angeles area and beyond, while leveraging Mariner’s national footprint and multi-disciplinary resources in advanced financial planning, investment solutions, tax, estate, trust, insurance, marketing enablement, and transition support — providing a strong foundation for long-term business growth.
About Mariner
Mariner is a privately held national financial services firm equipped with the experience to meet your modern wealth needs. Our advisors have access to in-house expertise covering everything from tax, estate, trust, and insurance to investment banking and valuation, so they can maximize time spent creating unified wealth plans with clients. By opening more windows of wealth, we can create opportunities to positively impact the lives of many. With this purpose, we intend to raise the bar for the entire industry. Founded in 2006 with $300 million in assets under advisement, Mariner and its affiliates now advise on over $577 billion in assets as of 6/30/25. Learn more at www.mariner.com.
About Promontory Wealth’s Founders
Kyle Briggs, CFA® and Joseph Thomason, CFA® each bring more than a decade of experience in wealth management. At their previous firms, they managed client relationships and led portfolio construction, asset allocation, trading, investment research, and portfolio analysis. Briggs is a graduate of the University of Southern California (B.S., Business Administration, Corporate Finance). Thomason is a graduate of Boston College (B.S., Finance).
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