Stablecoin holders sitting on idle capital are losing millions annually in potential returns, and a new partnership between Spark and BitGo is designed to fix that problem while keeping institutional money inside regulated custody. The integration lets qualified custodians and institutional clients earn yield on stablecoins like USDC and USDT without moving funds into decentralized finance (DeFi) protocols, a compliance headache that has kept most large allocators on the sidelines.

Why Are Institutions Missing Out on Stablecoin Yields?

The math is stark. An institution parking $100 million in USDC and earning nothing loses roughly $3.6 million per year in potential returns, according to Sam MacPherson, co-founder and chief executive of Spark, a lending protocol within the Sky ecosystem. That opportunity cost has been a major friction point for treasurers managing large stablecoin reserves. Banks and custodians have historically offered minimal or zero interest on stablecoin deposits, keeping spreads wide and returns concentrated with financial institutions rather than their clients.

BitGo, the largest independent digital asset custodian, went public on the New York Stock Exchange in January and held approximately $104 billion in assets for more than 1,500 institutional clients at the time of its IPO filing. The platform's integration with Spark Savings creates a narrow but meaningful pathway for those clients to earn yield without leaving qualified custody, a regulatory safe harbor that most treasurers require before deploying capital into any protocol.

The yield itself comes from multiple sources, including Treasury bill exposure on stablecoin reserves, on-chain crypto-backed loans, and an off-chain lending desk run with Anchorage Digital Bank, a federally chartered crypto custodian. This multi-layered approach allows Spark to offer returns while maintaining the high cash reserves needed for institutional-grade stability.

How Does Spark Maintain Bank-Like Safety Standards?

• Reserve Ratios: Sky maintains roughly 50 to 60 percent cash reserves against deposits, far exceeding the typical 10 percent that traditional banks hold, allowing institutions to withdraw hundreds of millions with no advance notice.
• Risk Framework: Spark follows a Basel-inspired risk model, the same framework that banks use for capital adequacy, ensuring that borrowed funds are monitored and positions can be liquidated if risk thresholds are breached.
• No Lock-Up Periods: The treasury tool is designed for withdrawal with no notice at any time, making it fundamentally different from yield farms that lock capital for extended periods.

MacPherson explained the structural difference between Spark and typical DeFi apps: "It's designed for you to be able to withdraw with no notice at any time". This flexibility is critical for institutional treasurers who need liquidity on demand. The protocol's ability to handle sudden large withdrawals without disruption mirrors traditional banking operations, not speculative DeFi mechanics.

Spark itself is the third-largest stablecoin issuer by market capitalization, with its USDS stablecoin holding roughly $8.7 billion in total value, behind Tether's USDT and Circle's USDC. The protocol closed May with approximately $6.4 billion in its Savings product and $3.4 billion in its SparkLend lending market, demonstrating meaningful scale and institutional adoption.

What Does This Mean for Banks and Stablecoin Regulation?

The BitGo integration has exposed a real tension in Congress and the banking industry. The GENIUS Act, signed by President Trump in July 2025, bars stablecoin issuers themselves from paying interest to holders. However, the law does not prevent third parties like exchanges and DeFi protocols from paying yield on stablecoins they did not issue. This regulatory gap is precisely where Spark and BitGo operate, and it has drawn fierce opposition from the banking lobby.

"Banks power the economy by turning deposits into loans. Incentivizing a shift from bank deposits and money market funds to stablecoins would end up increasing lending costs and reducing loans to businesses and consumer households," the Bank Policy Institute wrote in August.

Bank Policy Institute, August 2025

MacPherson dismissed this concern as defensive positioning. "We've already seen that the banks have been quite resistant about forwarding yield on stablecoins. It's precisely because they want to keep their high margins from depositors in banks," he stated. He predicted that the banking industry's opposition will ultimately fail, and that major banks will launch their own stablecoins in the near future as competitive pressure mounts.

The next regulatory battleground is the CLARITY Act, a market-structure bill that cleared the Senate Banking Committee in May with contested language on how far crypto firms can pay yield. This legislation will likely determine whether the Spark-BitGo model becomes a template for institutional stablecoin returns or faces new restrictions.

How Big Could the Stablecoin Market Actually Grow?

MacPherson estimates the current stablecoin market at around $300 billion and expects it to grow tenfold to $3 trillion within the next couple of years. This projection sits within Citigroup's published range of $1.9 trillion to $4 trillion by 2030, suggesting broad consensus among financial institutions that stablecoins will become a major pillar of global payments infrastructure.

Other blockchain leaders are betting heavily on this trajectory. Marc Boiron, chief executive of the Polygon blockchain network, has repositioned his entire chain around stablecoin payments, arguing that countries face competitive pressure to enable stablecoin flows or risk falling behind globally. The vision is one where users hold USDC, Ripple's RLUSD, or PayPal's PYUSD in a mobile app and earn yield by default, without needing to understand custody, DeFi, or protocol mechanics.

For now, yields remain thin because crypto lending demand is soft and basis spreads compress when trading activity declines. MacPherson acknowledged that "the crypto markets are quite dead" at present, which is why rates are low. But the infrastructure being built today, including the BitGo integration, is designed to scale when institutional demand returns and stablecoin adoption accelerates.

The real test of whether institutions will embrace this model lies in the next few months. If the BitGo pipe successfully attracts meaningful capital from qualified custodians and their clients, it will validate the thesis that stablecoin yield can compete with traditional banking products while maintaining institutional-grade safety and regulatory compliance. If adoption remains sluggish, it may signal that treasurers still prefer the simplicity and familiarity of traditional bank deposits, even at the cost of foregone returns.