Diamond Foundry.
The world's leading producer of single-crystal diamond — and the company solving the thermal bottleneck now constraining the next generation of AI compute.
Prepared for a select group of Barramundi clients. Figures reference the company's Q1 2026 disclosures and Barramundi's diligence file as of late April 2026.
An entry into the company that is putting diamond into AI chips for the first time in history — at the last secondary mark before the next round prices.
- What it is. Diamond Foundry is the world's leading producer of single-crystal diamond, founded 2012 by Stanford / Princeton / MIT engineers. The proprietary plasma reactor that grew the jewelry business now grows diamond wafers — the substrate that will be bonded to AI chips for thermal management.
- Why it matters. A diamond layer on a chip's hot spot delivers 4× compute power at 50% of the electricity, doubles useful life, and adds less than 5% to total chip cost. Every major hyperscaler is paying attention.
- Where it stands today. $233M revenue in 2025 (+63% YoY), EBITDA-positive, $515M lifetime raised over 14 years. Three manufacturing facilities operational; the Spanish wafer fab is funded with ~$1B of non-dilutive government capital.
- The catalyst. First commercial wafer production begins May 2026 at 30K wafers / month, supplying Google's next-generation TPU with Intel as fabricator. Architect of the deal: Lip-Bu Tan, who left the Diamond Foundry board to become Intel's CEO.
- The deal. Common stock secondary at $79 / share · $5.95B. The next round, anticipated Q3 2026 with participation from Nvidia, Microsoft, Amazon, Google, and Intel alongside Sequoia, Softbank, and QIA, is expected to price at approximately $196 / share · $18.5B — a ~2.5x mark-to-mark.
- The Barramundi allocation. $5M currently available to qualified clients. First-come, first-served. Closing imminently.
Allocation in this $40M secondary transaction is being offered to qualified Barramundi clients on a first-come, first-served basis.
The company.
Diamond Foundry was founded in 2012 by graduates of Stanford, Princeton, and MIT around a single proprietary invention — a plasma reactor that grows real, single-crystal diamond, atom by atom, from methane gas. For a decade, that reactor produced diamond ingots for jewelry. Today, reconfigured, it produces diamond wafers for AI chips.
The diamond Diamond Foundry grows is physically and chemically identical to mined stone but produced at industrial scale. That capability built a profitable jewelry operation — partnerships with Prada and TAG Heuer, the direct-to-consumer brand VRAI, and 2025 revenue of approximately $233M. Critically, that jewelry revenue funded seven years of wafer R&D without significant outside capital. The company has raised only $515M in fourteen years — a striking level of restraint for a hard-tech business of this scope.
Roughly seven years ago the team recognized that diamond's thermal conductivity is the highest of any material on earth. As frontier AI chips began dissipating hundreds of watts in a few square centimeters, that observation crystallized into a thesis: if the ingot reactor could be reshaped to grow flat, atomically uniform wafers, diamond could be bonded directly to the hottest spot of a semiconductor and pull heat away faster than any silicon or silicon-carbide alternative. The reactor exists. The wafers are now in production. The performance impact, validated by tier-one partners, is described in four numbers — each, in our view, the strongest single argument for why this opportunity exists.
Performance figures reflect company-validated bonding and thermal evaluation results with tier-one semiconductor partners. Independent third-party validation pending commercial production.
Three manufacturing facilities are in operation today: Diamond Foundry I in Wenatchee, Washington (ingot growth); Diamond Foundry II in Trujillo, Spain (ingot growth at scale); and the new Diamond Wafer Fab in Zaragoza, Spain — a 1-million-square-foot site dedicated entirely to wafer production. Total committed capital across the Spanish footprint is approximately $2.77B, of which roughly $1B has been provided by the Government of Spain and the EU as non-dilutive funding. First commercial output begins in May 2026 at approximately 30,000 wafers per month, supplying Google's next-generation TPU. Intel manufactures the chips that the diamond wafers are bonded to. The near-term scaling target is roughly 100,000 wafers per month within twelve months.
Why now.
Lip-Bu Tan, an early Diamond Foundry investor and a board member of ten years, stepped down from the Diamond Foundry board on March 12, 2025 to take the role of CEO at Intel. He has subsequently been the architect of the commercial relationship between Intel, Google, and Diamond Foundry that begins production in May. That single sequence of events tells you most of what you need to know about the company's positioning at this moment.
Diamond Foundry has communicated to Barramundi that its next financing round is anticipated in Q3 2026, targeted at approximately $1B, and expected to price at approximately $196 per share — an implied valuation of approximately $18.5B, or roughly 2.5x the current secondary mark. Anticipated participation from the financing round includes Nvidia, Microsoft, Amazon, Google, and Intel as strategic investors, alongside Sequoia, Softbank, and the Qatar Investment Authority as financial investors. The $40M secondary being offered today, sourced from the family-office investor with the largest existing position, is the only window to enter at the $5.95B mark before that round prices.
The company, in five minutes.
VideoOur thesis.
AI compute is now thermally bound. Frontier accelerators dissipate hundreds of watts in a few square centimeters; for the next generation, packaging — not photolithography — is the limiting factor. Diamond is the only material in the periodic table with thermal conductivity high enough to relieve that constraint, and Diamond Foundry is the only company manufacturing it at semiconductor scale today. Six observations support our underwriting.
Diamond solves the binding constraint of the AI cycle.
Diamond has roughly 15x the thermal conductivity of silicon — the highest of any known material. A thin layer between the silicon die and the package allows chips to operate up to 3x faster without overheating, addressing the most acute scaling bottleneck in advanced computing.
A roughly two-year wafer-scale lead.
The company produced the world's first 100mm monocrystalline diamond wafer in 2023, has scaled to 200mm, and has deployed the growth reactor for 300mm — the standard semiconductor wafer size. Our diligence places the nearest competitor approximately two years behind.
Validation from the people who matter most.
Google included "Diamond on Chip" in the public specifications of its next-generation TPU at SEMICON Taiwan in September 2025. Intel serves as the silicon fabricator for the chips entering production in May. This level of acknowledgement from the buyers themselves is uncommon at this stage.
Asymmetric entry economics.
Common stock at $79 / share implies a $5.95B mark today. Indicated terms for the company's anticipated Q3 2026 round imply pricing of approximately $196 / share, a $18.5B mark — roughly 2.5x the current entry. Diamond Foundry has raised only $515M across its fourteen-year life, an unusual level of capital efficiency for a hard-tech business of this scope.
By the numbers.
Wafer-scale progression.
Diamond at semiconductor wafer scale has historically not existed. Diamond Foundry produced the world's first 100mm monocrystalline diamond wafer in 2023, scaled to 200mm in 2024–25, and has now deployed the reactor for 300mm — the industry-standard size. The company's nearest competitor is roughly two years behind on the same axis.
External validation.
The clearest signal in any deep-tech investment is whether the eventual buyers are paying attention. In this case, the buyers have begun saying so on the record.
The next decade of computing will be limited by what can be cooled, not what can be etched. Diamond Foundry is the only company we have found at the substrate layer of that problem.— From Barramundi's Diamond Foundry investment memorandum
Entry, and outlook.
The economic case for entering at the current mark is best read as a comparison: the price at which clients can participate today, against the price at which the company's anticipated next round is expected to clear, based on round terms communicated to Barramundi.
Common stock is junior to preferred in the capital stack. The next-round figure reflects round terms communicated to Barramundi by the company and has not been independently confirmed in writing. Underwriting case figures are forward-looking and may not materialize.
The cap table.
Diamond Foundry's existing institutional and strategic backers, in our view, are an unusually high-quality reading of who has been able to evaluate the substrate-layer opportunity in advance.
Anticipated next-round participants are listed in the valuation outlook section above. We are happy to discuss syndicate composition in greater detail by phone with qualified clients.
A candid note on risk.
- Common stock is junior in the capital stack. Investors entering through this structure stand behind preferred holders in any liquidation, and rely on the equity story for return.
- The May 2026 first-commercial-output milestone is the central catalyst. Slippage in this timeline — or in the planned scaling from 30,000 to 100,000 wafers per month over the following twelve months — would materially affect the underwriting case for the Q3 2026 next round and the implied mark-up on entry.
- Volume ramp execution. The company's own Q4 2025 update flagged being behind plan on wafer chip plate volume ramp. We are tracking this closely; further slippage would compress the path to commercial production and the next-round catalyst.
- Customer concentration. Public validation from Google and Intel is a strong signal but creates dependency on the timing and scale of programs at a small number of hyperscaler and chipmaker customers.
- Substrate-layer competition. Silicon-carbide interposers and other thermal-management approaches compete for the same architectural slot. Diamond's physics advantage is clear; commercial economics at scale are still being proven.
- Lab-grown diamond price decline. The legacy gem business faces structural pricing pressure as synthetic diamond capacity expands globally. We do not underwrite the gem business as a source of return.
- Sovereign timing risk. Spain's $983M non-dilutive commitment is contingent on milestones and disbursement schedules typical of government programs; non-linearity is to be expected.
- Valuation has moved quickly. Investors entering at the current mark are underwriting further multiple expansion driven by the commercial-integration catalyst. The next-round figures referenced here are based on terms communicated to Barramundi but have not been independently confirmed in writing.
- Private-market liquidity is limited. Secondary exit timing is uncertain and may be materially longer than in comparable late-stage technology investments.
Next steps.
If the thesis resonates, there are two ways to go further. Register your interest and a member of Barramundi's team will be in touch within the day to discuss subscription mechanics, signing logistics, and any remaining diligence questions. Or review the full file at your own pace in our Box data room.