Mercer Advisors, Inc. (“Mercer Advisors”), a national wealth management and financial planning firm, today announced the acquisition of Fifteenth, an artificial intelligence (AI)-native tax and accounting firm whose proprietary platform is purpose-built for equity compensation and complex tax situations. The transaction reinforces Mercer Advisors commitment to put practical AI and technology to work for clients to better deliver comprehensive, integrated family office services including financial planning, tax planning and preparation, estate planning and investment management.

Fifteenth’s team brings tax expertise from Big Four and other leading firms, paired with a proprietary AI platform built specifically for high-complexity tax work. The firm combines annual tax preparation with year-round planning, helping clients navigate stock option exercises, tender offers, liquidity events and multi-entity filings. Fifteenth has a strong following among employees of Silicon Valley technology firms. Its AI-focused tech builders join Mercer Advisors, as the firm continues to invest in leading talent who want to do meaningful work that bridges financial services and technology.

“Fifteenth combines personalized, high-touch service with the power of modern software, and we are excited to bring our specialized tools that are already serving more than 1,000 professionals to more families through our partnership with Mercer Advisors,” said Ankur Dahiya, CEO and Co-Founder, Fifteenth.

Tax services remain in high demand among clients, and Fifteenth’s technology and team add both capacity and capability. More than half of the ultra-high-net-worth clients who join Mercer Advisors are actively seeking tax capabilities as part of a unified offering, a trend the firm attributes to rising wealth complexity and a wave of executive equity and liquidity events across fast-growing companies. Tax professionals now make up roughly one in 10 of the firm’s employees, a share expected to reach one in eight by the end of 2026. Fifteenth’s technology can help those teams support more clients with complex needs, consistent with the firm’s approach of adding high-quality, fiduciary-minded professionals and specialized capabilities that deepen what it can deliver to clients over the long term.

“What sets Fifteenth apart is that their AI capabilities aren’t theoretical. They’ve been built and refined through supporting thousands of returns, real numbers that made us excited about bringing their time-tested technology into our organization,” said Cynthia Loh, Chief Platform Officer of Mercer Advisors. “As we integrate their tools alongside our existing tax infrastructure, we expect to meaningfully expand the capacity of our tax teams while continuing to deliver the high level of expertise and service our clients expect. Just as important, Fifteenth’s team joins a firm where talented technologists can build practical AI that makes a real difference for clients. We want Mercer Advisors to be the home for great tech talent that wants to do meaningful work.”

Fifteenth’s focus on equity compensation adds depth in an area where tax and wealth planning frequently intersect. It also creates opportunities to engage clients earlier, supporting strategy well ahead of a sale, initial public offering (IPO), or other major liquidity event – not just at filing time. The addition of Fifteenth’s technology and CPA team also deepens the support available to a subset of Mercer Advisors’ existing tax clients, who increasingly face similar complexity.

“We built Fifteenth around a simple idea: even the most complex tax situations shouldn’t have to feel complex for the client. Technology is a huge part of how we deliver on that promise, but so is the judgment of experienced tax professionals,” said Laura Moreno, Chief Tax Officer and Co-Founder, Fifteenth. “Joining Mercer Advisors gives us the opportunity to bring that combination to more clients at greater scale. And for our existing clients, it means the tax experience they know can now connect to comprehensive wealth management, giving them a deeper context for Economic Freedom™.”

“We are excited to welcome Fifteenth’s team to the partnership. They created Fifteenth to combine sophisticated tax support with AI-driven solutions for tax professionals,” said Daniel Gourvitch, President of Mercer Advisors. “Our partnership strategy is ultimately about building a better experience for clients, and technology that works in partnership with high-caliber professionals is a significant part of that. Fifteenth fits that model with a tax focus and technology that can be extended to the clients who need it.”

Mercer Advisors is focused on using AI tools and technology to support its teams in serving clients. In the summer, it announced the second generation of Aspen, its AI-enabled platform used by its wealth advisory teams.

For more information on Mercer Advisors, please visit merceradvisors.com.

About Mercer Advisors

Mercer Global Advisors, Inc. was named the #1 ranked RIA firm in the nation for the last three years by Barron’s Top 100 Registered Investment Advisor Firms rankings. It is also distinguished as the Best Overall Financial Advisory Firm for High-Net-Worth Individuals 2026 by The Wall Street Journal Buy Side. Founded in 1985, Mercer Advisors has been trusted to help families amplify and simplify their financial lives. The company offers comprehensive, fee-based family office services, including financial planning, estate and tax planning, insurance solutions, and corporate trustee and trust administration services. Mercer Advisors is majority owned by Oak Hill Capital, Genstar Capital, Altas Partners and GIC. Mercer Global Advisors Inc. is headquartered in Denver, Colorado, is privately held, has 1,880+ employees, and operates nationally through more than 120 locations. Mercer Global Advisors has $114 billion in client assets. For more information, visit merceradvisors.com and partnerwithus.merceradvisors.com/.

Important Information

Company statistics as of September 30, 2026. Client assets refers to client assets under management (AUM) and client assets under advisement (AUA) as well as assets gained from recent acquisitions where the advisory agreements have been properly assigned to Mercer Global Advisors, but the custodial accounts have yet to be transferred and/or the accounts have yet to be migrated to Mercer Global Advisors’ portfolio management system.

“Mercer Advisors” is a brand name used by several affiliated legal entities owned by Mercer Advisors, Inc., including, Mercer Global Advisors, Inc., an SEC registered investment adviser providing investment advisory and family office services; Mercer Advisors Private Asset Management, Inc., an SEC registered investment adviser providing discretionary investment management services to affiliated private funds; Mercer Advisors Tax Services LLC, a tax services and accounting firm; Heim, Young and Associates, Inc., (MA Brokerage Solutions) a broker/dealer, member FINRA/SIPC; and Mercer Advisors Insurance Services LLC, (MAIS) an insurance agency.

Mercer Advisors is not a law firm and does not provide legal advice to clients. All Estate planning document preparation and other legal advice are provided through select third parties, with which Mercer Advisors has a contractual relationship. Tax preparation and filing services are provided by Mercer Advisors Tax Services, LLC. Clients will sign a separate agreement when engaging Mercer Advisors Tax Services that defines the services provided and any additional fees that may apply. Insurance products are provided by Mercer Advisors Insurance Services, LLC (MAIS), which places individual life, disability, long term care coverage, and property and casualty coverage through select insurance companies. Trustee services are offered through select third parties with which a client would sign an additional agreement, and additional fees may apply.

2026, 2025 and 2024 – Barron’s Top 100 RIA methodology

Mercer Global Advisors, Inc. was ranked #1 for non-mega RIA firms. Advisers who wish to be ranked fill out a 100+ question survey about their practice. Barron’s verifies that data with regulatory databases and then Barron’s applies their rankings formula to the data to generate a ranking. The formula features three major categories of calculations: (1) Assets (2) Revenue (3) Quality of practice. In each of those categories Barron’s does multiple sub calculations including asset type, growth, client retention, technology spending, succession planning, diversity of their teams, charitable and philanthropic work and compliance records. The rankings are awarded each September based on prior 12-month data through June 30th. No fee was paid for participation in the ranking, however, Mercer Advisors has paid a fee to Barron’s for logo licensing.

2026 Wall Street Journal Buy Side – Best Overall Firm for High-Net-Worth Investors

Buy Side analyzed some of the largest and best-known independent registered investment adviser (RIA) firms and scored those firms based on their fees, advisor credentials, customer support, available services, portfolio construction and account minimum. These factors were weighted based on WSJ reader surveys regarding what they considered most important when choosing an advisor. Prioritized, were firms that have a client base of 50% or more HNWIs according to their most recent Form ADV filing. To be considered a top financial advisor for high-net-worth individuals, a firm has to offer comprehensive wealth management services. Firms were rated on a scale of 1 to 5 stars using a weighted scoring model out of 100 possible points. A 5-star rating represents top performance relative to the field, rather than a requirement to achieve a theoretical perfect score of 100.

Please Note: Limitations. Neither rankings and/or recognitions by unaffiliated rating services, publications, media, or other organizations, nor the achievement of any professional designation, certification, degree, or license, membership in any professional organization, or any amount of prior experience or success, should be construed by a client or prospective client as a guarantee that they will experience a certain level of results if Mercer Advisors or its investment professionals are engaged, or continues to be engaged, to provide investment advisory services. A fee was not paid by either Mercer Advisors or its investment professionals to receive the award or ranking. The award or ranking is based upon specific criteria and methodology. No ranking or recognition should be construed as an endorsement by any past or current client of Mercer Advisors or its investment professionals.

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