Mike Castino on Market Makers, Platform Fees, and Building a Boutique ETF Firm

In this episode of the Rainmaker Podcast, Gui Costin sits down with Mike Castino, President of Sound Capital Solutions, for a deep dive into the mechanics of ETF creation, distribution, and the accelerating structural shift reshaping investment management. Mike's career began on the floor of the Chicago Mercantile Exchange, where he spent 12 years as an independent futures trader before transitioning into the investment management industry. His first sales role came at Claymore ETFs — one of the original ETF families, eventually acquired by Guggenheim and later Invesco — where his trading floor instincts translated directly into his commercial style. From there, Mike spent over a decade at U.S. Bank Global Fund Services, building out the business development function for ETF administrative and custodial services from the ground floor into a high-revenue operation. Sound Capital, the firm he co-founded with Claymore veteran Nick Dalmasso, was born from a shared entrepreneurial itch and a clear view of where the industry was heading. Sound Capital operates two complementary businesses: a white label ETF advisory service, where the firm serves as the registered advisor for clients who want to launch funds without building their own infrastructure, and a solutions provider offering that supports asset managers before, during, and after launch. Unlike traditional consultants who parachute in with a plan and leave, Sound Capital positions itself as a long-term partner focused on helping clients both build and retain AUM. A major theme of the conversation is the mechanics behind getting an ETF to market — and the parts that most first-time issuers underestimate. Revenue sharing with broker-dealer platforms is more complex and more negotiable than it appears, with fees ranging from flat access charges to AUM-based percentages to paid data packages. Market maker relationships are similarly misunderstood: firms like Jane Street and Citadel are not standing by as utilities for any issuer that arrives. They are selective partners who respond to seed capital, credible distribution plans, and meaningful trading relationships. Mike and Gui also discuss the transparent versus non-transparent active ETF debate, where Mike is direct: the flows have settled the argument. Non-transparent structures have failed to gather meaningful organic assets, while transparent active ETFs have surged — and the front-running fears that once justified opacity are largely overstated for anyone outside of micro-cap strategies. The conversation closes on two forward-looking topics. First, the dual share class structure — now approved for 30+ firms beyond Vanguard — which Mike sees as the long-term bridge that will unlock sticky mutual fund assets as intermediaries build switching infrastructure. Second, the challenge of building a young firm's credibility in a market that prizes institutional tenure. Mike is candid: individual experience only goes so far when prospects are evaluating the firm itself, and the answer is simply to deliver exceptional work, every day, one client at a time. Tired of chasing outdated leads? Book a demo to see how Dakota Marketplace simplifies your fundraising process with accurate, up-to-date investor data. Click here to book a demo today ➡️ https://www.dakota.com/calendar-website