SandboxAQ has $950M on record. The latest round is a $450M Series F (May 2026). Size your own round against the evidence it must buy, not against the stage letter.
Key takeaways
- Round size should be derived from the evidence the next investor needs, not from the stage label.
- Named participants on a record tell you which funds write at this size and stage.
- Plan the raise timeline backwards from your cash-out date, with a third added for slippage.
Founders outside the main US hubs face a real choice: raise locally at terms set by a smaller pool, or spend months building conviction with funds several time zones away.
The record here belongs to Jack Hidary, founder of SandboxAQ (Mountain View, California).
| | | |---|---| | Founder | Jack Hidary | | Company | SandboxAQ (Mountain View, California) | | Total raised | $950M | | Latest round | Series F — $450M | | Round date | May 2026 | | Named participants on record | Schmidt, Breyer Capital, T. Rowe Price, TIME Ventures, Ray Dalio, Horizon Kinetics |
This round is 47% of everything raised to date, so earlier rounds still shape the cap table.
The round size sets the next evidence bar. Investors size the following round against what this one was expected to buy. Write that expectation down before you sign.
Named participants signal the buyer pool. Schmidt, Breyer Capital, T. Rowe Price, TIME Ventures, Ray Dalio, Horizon Kinetics are on record here. Funds with that profile are the realistic audience for a comparable raise.
Timing is data. The round closed in May 2026. Fundraises take longer than founders plan; count backwards from the date you need cash, not from the date you want a term sheet.
1. Write the two or three pieces of evidence your next round must show. 2. Cost out the months and headcount required to produce that evidence, then add a third for slippage. 3. Build the investor list from funds that have written cheques of this size at this stage, not from brand preference. 4. Ask each lead what they expect to see at the next round, and hold them to it in writing.
The letter on the round matters far less than whether the money buys the evidence the next buyer needs.
Frequently asked questions
- How much has Jack Hidary raised for SandboxAQ?
- SandboxAQ has $950M in disclosed funding on record, most recently a $450M Series F in May 2026.
- Who invested in SandboxAQ?
- Named participants on record include Schmidt, Breyer Capital, T. Rowe Price, TIME Ventures, Ray Dalio, Horizon Kinetics. Records list participants, not allocations or terms.
- Where do these figures come from?
- Structured founder funding records: total raised, round stage, round amount, round date and named participants. They exclude valuation, terms and board composition.
