What It Took to Get SB Energy's S-1 Through SEC Review

SB Energy is the SoftBank-controlled developer that builds, owns, and operates utility-scale solar and battery storage (about 2.2 GWac in operation at June 30, 2026) and is now constructing AI data center campuses to lease to SoftBank and OpenAI. It filed its Form S-1 on September 1, 2026, with $213.5 million of total revenue in 2025 and a valuation that Reuters has reported could exceed $50 billion, on the strength of roughly $439 billion of backlog, about $430 billion of it for data centers. Per its own prospectus, "No data center capacity is currently in operation." 

What it does have is some incredibly complex accounting and a web of related parties. We tasked UpDraft with breaking down the S-1. Here's what we found, and what it tell us about IPO readiness today.

The positions

OpenAI warrants

In January 2026, alongside the Milam County data center leases, the company issued warrants to OpenAI at a nominal exercise price with a ten-year term. They vest on lease execution, development milestones, and equity valuation thresholds, with one tranche vesting only on the IPO, and on vesting each warrant exchanges into a warrant on the parent's equity rather than the registrant's. The company classifies the package as a liability under ASC 480 and ASC 815, carried at about $5.5 billion at June 30, 2026. The six-month remeasurement produced a $2.6 billion non-cash expense, most of the period's $3.2 billion net loss, and because the warrants went to a tenant, their initial cost is treated as a lease incentive that will reduce revenue once the leases commence.

Why it's complex:

• Equity versus liability classification for an instrument that settles in the parent's equity, not the registrant's, and carries both performance and IPO vesting conditions.
• Characterizing the warrants as consideration payable to a customer (a lease incentive) rather than a financing cost or compensation, and deferring that incentive until lease commencement.
• Probability assessments on the performance-vesting tranches drive how much liability is recognized each period.
• Level 3 measurement that depends on an equity value for a private parent, derived by weighting an IPO scenario against a transaction scenario.
• Settlement of vested warrants at the parent level is pushed down to the registrant as a capital contribution.

Tax equity partnerships

The solar business is financed through eight consolidated tax equity variable interest entities holding about $3.1 billion of assets. Third-party investors are allocated earnings, tax attributes, and distributable cash under each LLC agreement, and many agreements include a mechanism that steps up cash distributions if the investor has not hit its target return by a specified date. Noncontrolling interests are measured under the hypothetical liquidation at book value method, so each period's allocation depends on estimated taxable income, tax capital accounts, and whether investment tax credits were recognized.

Why it's complex:

• Primary beneficiary determination for each of the eight structures.
• HLBV mechanics run on estimated taxable income, ITC recognition, and accelerated depreciation, producing large period-to-period swings in what is allocated to noncontrolling interests.
• Where tax benefits are used outside the arrangement, the difference between the contractual liquidation and actual distributions is amortized over a "systematic and rational" period the company has to define.
• Mezzanine versus permanent equity classification of noncontrolling interests where investor return mechanisms exist.

Derivatives in revenue

Of the $213.5 million of revenue reported for 2025, $70.5 million was the realized and unrealized change in fair value of power price swaps: fixed-for-floating contracts on specified quantities, settling monthly, valued on forward power curves. During the second quarter of 2026, a set of embedded swaps inside capacity contracts entered derivative accounting only because construction permits were obtained and the predominant underlying shifted to market price. Contracts that qualify as normal purchases and normal sales stay off the mark-to-market.

Why it's complex:

• Derivative scope determination for physical and financial power agreements and capacity arrangements, including the normal purchase normal sale exception.
• Identifying and bifurcating embedded derivatives in capacity contracts, and pinning down the date a contract enters ASC 815 scope (here, tied to permit receipt).
• Level 3 valuation of 15-year contracts on long-dated hourly power price forecasts.

Data center leases

Three executed lease arrangements sat on the books at June 30, all with SoftBank or OpenAI affiliates as tenant, none commenced under ASC 842 because the buildings are still under construction. Rent is set on a yield-on-cost basis with escalators, initial terms run about 15 years with renewal options, the weighted average remaining contract length is 19.6 years, and the Milam County leases carry contingent buy-out rights if ready-for-service conditions are missed. Nvidia sits on the PORTS-Pike campus as residual value guarantor, and it also prepaid $1.5 billion under a forward contract that settles at the IPO in shares priced at 90% of the offering price.

Why it's complex:

• Lease classification (sales-type, direct financing, or operating) for build-to-suit assets with yield-on-cost rent, long terms, renewal options, and a third-party residual value guaranty.
• Determining lease commencement and the treatment of construction-period costs, tenant-specific design, and the OpenAI warrant lease incentive that will reduce lease revenue.
• Accounting for the contingent buy-out rights and tenant acceptance conditions, and what they mean for the $439 billion backlog figure.
• Related-party counterparties on every executed lease, with parent-level completion guaranties layered on top.
• A prepaid forward with a variable share count, a 10% discount to the IPO price, a cash-settlement alternative, and an obligation issued by the parent but assumed by the registrant.

Material weakness

The company disclosed what that workload did to its control environment. The S-1 reports a material weakness in internal control over financial reporting: controls "were not operating effectively to appropriately evaluate the accounting for significant complex transactions and to appropriately assess the related financial statement presentation and disclosure requirements." As of June 30, 2026, it had not been remediated.

Read that language against the transactions above. The weakness sits precisely in the evaluation of complex transactions, which is the judgment layer, at a company with SoftBank's resources, Deloitte as auditor, and a $50 billion offering in progress. Even with that backing, the company could not staff enough evaluative capacity to satisfy its own control framework.

What SEC review demands of a technical accounting team

The filing history on EDGAR shows how long the review ran. SB Energy submitted a confidential draft registration statement on May 22, 2026, amended it on June 23 and again on July 22, and filed publicly on September 1. Deep Quarry and The Dig compared the first draft with the public S-1 and found thousands of changes, with the material revisions concentrated where SEC reviews concentrate: risk factors around tenant termination and buy-out rights and what those rights mean for the backlog figure, disclosure of estimated revenue remaining under contract, and related-party transactions.

The S-1 defines backlog as "the estimated revenue remaining to be recognized over the life of our executed and binding customer contracts." Every redline touching that definition was a decision about whether a $439 billion figure, resting on leases with buy-out rights and tenants who are also investors, informs or misleads.

That review is narrower than it used to be. SEC Chair Paul Atkins has framed his agenda as an effort to make IPOs great again, in part by holding disclosure review to a standard of materiality rather than checklist completeness. Fewer comments on immaterial items means the comments concentrate on the big technical positions and related disclosures. SB Energy's comment letters should become public around the end of September, and it’s safe bet where most of their focus landed.