The public-private funding record is the set of eleven DOE technical reports deposited with OSTI between 2022 and 2025, plus a 2026 recorded seminar, that document what Commonwealth Fusion Systems has built jointly with national laboratories and universities on federal money.
It is grey literature — unrefereed, deposited rather than published — and it is where the engineering roadmap is visible in a way the journal record does not show, because a final report states what a project set out to do, who paid for it, and what came back. The sponsors are more varied than the 📝INFUSE label suggests: 📝ARPA-E fusion programs, the DOE Office of Science and its Fusion Energy Sciences program (which runs INFUSE), and the National Nuclear Security Administration all appear. None of these are awards under the 📝DOE Milestone-Based Fusion Development Program, which is a separate instrument.
The magnet strand is one report and the largest single claim in the set. "Pulsed High Temperature Superconducting Central Solenoid for Revolutionizing Tokamaks" (10.2172/2554023, ARPA-E award AR0001259, December 2023) records CFS's technical foundation for a fast-ramping HTS 📝central solenoid model coil, with 📝Bob Mumgaard among the authors; the report projects 50% lower electricity cost and 25% lower overnight construction cost for an all-HTS pulsed tokamak plant, which is a project projection rather than a measured outcome.
Three reports are plasma physics support bought from the laboratories. Nikolas Logan of Lawrence Livermore led the SPARC 3D field physics and non-axisymmetric coil assessment (10.2172/1860838, NNSA, January 2022) with 📝Carlos Paz-Soldan of 📝Columbia Fusion Research Center, 📝Alex Creely and 📝Ryan Sweeney. Andreas Wingen of 📝Oak Ridge National Laboratory led the M3D-C1 study of 📝edge localized mode (ELM) mitigation by 📝pellet injection in low-collisionality 📝SPARC discharges with Andreas Kleiner of 📝Princeton Plasma Physics Laboratory, 📝Tom Looby, 📝Thomas Eich and 📝Jon Hillesheim — deposited twice, as 10.2172/2998008 and 10.2172/3002040. Jeremy Lore of ORNL led time-dependent SOLPS boundary modelling to inform SPARC diagnostic and actuator design (10.2172/2000338, 2023) with Creely, 📝Adam Kuang and 📝Matt Reinke.
Four are materials and manufacturing. Travis Gray of ORNL led divertor component testing (10.2172/1993696, 2022) with Reinke and Kuang, opening from the empirical scaling that puts unmitigated boundary heat flux in SPARC above 10 GW/m². Jaime Marian of UCLA led the INFUSE project informing 📝ARC divertor design and plasma-facing material selection (10.2172/2589555, award SC0024662, final September 2025) with Lauren Garrison of CFS; the report finds in simulation that 📝tungsten–rhenium alloys resist grain growth better than pure tungsten and that hydrogen buildup depends more on particle flux than on temperature. Andrzej Nycz of ORNL led advanced manufacturing workflows for tokamak internal components (10.2172/2281121, 2023) with Deepthi Tammana, Shiyun Ruan and Cody Dennett of CFS, and Xiao Li of Pacific Northwest National Laboratory led an INFUSE CRADA on oxide-dispersion-strengthened ferritic steel wire feedstock for large-format additive manufacturing (10.2172/3006354, April 2025), also with Dennett.
Two are blanket engineering, both on 📝molten salt. Luke Olson of Savannah River National Laboratory led active redox control of molten salts for fusion blankets (10.2172/2998318, 2023) with Caroline Barthel of CFS, addressing 📝FLiBe chemistry; Alexander Melin of ORNL led magnetic bearing pumps for molten salt fusion devices (10.2172/3002665, August 2025) with Matthew Vernacchia of CFS, for the ARC liquid immersion blanket in which the salt is both breeder and vacuum vessel coolant. Felix Parra Diaz of PPPL led the eleventh report, on US–UK fusion energy collaborations in the digital space (10.2172/2377254, NNSA, June 2024), with Jayesh Deshpande of CFS among the authors.
The twelfth item is not a report. "ARC Fusion Power Plant Physics Basis" (10.52843/cassyni.0nz3mr, 4 June 2026) is a recorded seminar by Hillesheim, Eich, 📝Nathan Howard, 📝Nils Leuthold and Sweeney presenting the five-paper set behind 📝The ARC Physics Basis (2026) — the ARC V3A design point of 11.4 T on axis, 12.0 MA of plasma current, R₀ = 4.62 m, a = 1.18 m, about 1.13 GW of D-T fusion power and at least 400 MW net electric. Every one of those is a design value for a plant not yet built.
ARPA-E paid for the pulsed central solenoid work, INFUSE paid for the ARC divertor materials modelling, and the labs did the SPARC 3D-field and boundary studies alongside us. The reports are public, and they show which parts of the roadmap we did not build alone.