Q1 13Fs show Mubadala adding IBIT as Harvard cuts again and exits ETH ETF
Filings as of March 31 reveal a split: sovereign exposure grew in bitcoin ETFs while one major endowment reduced risk across BTC and ETH sleeves.
A wave of Q1 13F filings due May 16 shows institutional crypto ETF positioning moving in two directions. Mubadala added to BlackRock’s iShares Bitcoin Trust (IBIT) while Harvard cut IBIT again and fully exited a recently opened BlackRock spot Ethereum ETF position.
Key Takeaways
- Mubadala lifted its IBIT position to 14,721,917 shares as of March 31, up from 12,702,323 shares previously, with the stake described as worth nearly $660 million at current prices.
- Harvard’s endowment reported 3,044,612 IBIT shares as of March 31, roughly $117 million, after a 43% reduction from its 5.35 million-share position at year-end 2025.
- A new BlackRock spot Ethereum ETF allocation was fully unwound by Harvard in Q1, exiting an $86.8 million position initiated the prior quarter.
- Dartmouth added a 304,803-share position in the Bitwise Solana Staking ETF while keeping its IBIT holdings unchanged at 201,531 shares.
Q1 13Fs Put Sovereign Funds and Endowments on Opposite Sides of IBIT
The May 16 SEC deadline for 13F filings delivered a clean snapshot of how large managers were positioned in U.S.-listed crypto ETFs as of March 31. The headline read-through for traders is divergence, not consensus.
On one side, Abu Dhabi-based Mubadala increased exposure to BlackRock’s iShares Bitcoin Trust (IBIT). On the other, Harvard’s endowment continued to reduce the same vehicle and also removed a newly established Ethereum ETF sleeve entirely. The filings land after a quarter that included a drawdown in crypto-linked risk, which matters because 13Fs capture quarter-end positioning rather than today’s exposure.
The Biggest IBIT Moves: Mubadala Adds, ADIC Holds Steady, Harvard Cuts Again
Mubadala reported 14,721,917 IBIT shares as of March 31, up from 12,702,323 shares previously. The position was described as worth nearly $660 million at current prices, though the share count is the only figure explicitly tied to the quarter-end date.
A separate Abu Dhabi complex showed why traders should be careful with “position value” headlines. The Mubadala-owned Abu Dhabi Investment Council (ADIC) kept its IBIT share count unchanged at 8,218,712 shares, valued at $315.8 million as of March 31. The filing attributed an approximately $92 million drop in value to IBIT’s quarterly decline rather than selling. It also noted a reporting change where Al Warda Investments’ position would now be reported through ADIC while the beneficial owner remained the same.
Harvard moved the other way. The endowment disclosed 3,044,612 IBIT shares as of March 31, worth roughly $117 million, a 43% cut from 5.35 million shares at the end of 2025 after already trimming 21% in Q4 2025. In market-structure terms, that is a sustained de-risking pattern rather than a one-off rebalance.
Endowment Positioning Broadens: Harvard Drops ETH ETF, Dartmouth Adds Solana Staking ETF
Harvard’s Q1 filing also showed a full exit of an $86.8 million BlackRock spot Ethereum ETF position that had been initiated only the prior quarter. The specific ticker was not identified in the filing details provided, but the practical implication is clear: ETH beta was removed alongside the continued reduction in IBIT.
Dartmouth’s disclosure cut the other way on breadth. It kept its IBIT position unchanged at 201,531 shares (a little over $9 million) and disclosed a new 304,803-share position in the Bitwise Solana Staking ETF worth almost $3.67 million. That is a concrete example of an endowment adding a non-BTC, non-ETH ETF sleeve while leaving its bitcoin ETF allocation intact.
Signals Traders Can and Can’t Take From 13Fs
13Fs are useful for identifying who is willing to warehouse exposure through a quarter-end and who is actively reducing it. They are not real-time flow.
The near-term check is whether spot BTC and spot ETH ETF daily creations and redemptions after the May 16 filing wave line up with the positioning implied by these disclosures. The next hard confirmation point is the Q2 reporting cycle, with holdings as of June 30 and filings due mid-August, which will show whether Harvard continues cutting and whether Mubadala keeps adding.
Price and liquidity still matter more than the optics. ADIC’s unchanged share count paired with a lower reported value is a reminder that IBIT price and volume behavior around large-flow sessions can drive headline “value” changes without any underlying selling.
What This Split Positioning Suggests for BTC/ETH/SOL Proxies
I treat this batch of filings as a positioning split, not an institutional stampede. The threshold that matters is follow-through in Q2: if Mubadala continues to add while Harvard keeps reducing, the setup starts to look structural rather than narrative-driven, with sovereign balance sheets acting as a steadier bid than endowment risk budgets.
The real test is whether ETF flow data confirms the same directionality in real time, especially for ETH where Harvard’s full exit reads like a risk-off decision rather than a tactical trim. If SOL-related endowment disclosures broaden beyond Dartmouth’s small Bitwise Solana Staking ETF sleeve, that would matter because it signals expanding institutional comfort with non-BTC beta in an ETF wrapper.
