On July 8, 2025, Rex‑Osprey's innovative Solana + Staking ETF (ticker SSK) recorded a massive $21 million net inflow—doubling its cumulative assets under management to $41.2 million, according to data from Farside Investors. This one-day influx represented a 104% increase against the $20.2 million amassed in the preceding three trading sessions, signaling a growing appetite for altcoin-based structured investments.

Launched on July 2, SSK combines spot SOL exposure with staking yield—at least 40% is allocated through foreign Solana ETFs under the Investment Company Act of 1940, with the rest directly invested in SOL. With a 0.75% management fee, the fund is pricier and far smaller than its Bitcoin and Ethereum counterparts—its early inflows equate to just 0.05% of SOL’s market cap, compared to 0.3–0.34% at launch for BTC and ETH ETFs.

Key Implications

1. Growing Altcoin ETF Demand

While Solana’s inflows are modest, the rapid doubling indicates rising investor confidence in altcoin strategies beyond Bitcoin and Ethereum. The structure also shows creativity in meeting regulatory requirements while delivering staking benefits.

2. Competitive Cost Dynamics

SSK’s 0.75% fee—higher than the ~0.25% charged by Bitcoin/ETH rivals—is a potential barrier. Its modest seed size (only $600K) implies limited liquidity through authorized participants.

3. Catalyst for Spot Solana…