A non-GAAP financial measure is a number a company reports that departs from the figures defined by U.S. generally accepted accounting principles — adjusted EBITDA, adjusted gross margin, free cash flow, and similar metrics that add back or exclude certain items management considers non-representative. These measures are common in the energy-storage sector, where companies routinely present adjusted profitability to strip out items such as stock-based compensation, restructuring charges, or one-time costs. A non-GAAP reconciliation is the disclosure that connects such an adjusted number back to the GAAP figure it is derived from, showing each adjustment so a reader can see exactly what was added back or excluded to get from the audited GAAP measure to the company-preferred one.

The reconciliation is not optional or merely a best practice; it is mandated by the Securities and Exchange Commission. In adopting Regulation G, the SEC required public companies that disclose non-GAAP financial measures to present, in the same disclosure, the most directly comparable GAAP measure and a reconciliation between the two. The final-rule release states the requirement directly.

"…Regulation G, which will require public companies that disclose or release such non-GAAP financial measures to include, in that disclosure or release, a presentation of the most directly comparable GAAP financial measure and a reconciliation of the disclosed non-GAAP financial measure to the most directly comparable GAAP financial measure."— SEC, Regulation G final rule (Release 33-8176), source

What Regulation G requires, and where Item 10(e) goes further

Regulation G applies broadly — to public disclosures and releases of non-GAAP measures, including earnings releases furnished to the SEC — and its core obligation is the pairing the release describes: present the most directly comparable GAAP measure, and reconcile the non-GAAP measure to it. Regulation G also includes a general anti-fraud-style prohibition: a non-GAAP measure may not, taken together with the accompanying information, be misleading. Alongside Regulation G, the same SEC action amended Item 10 of Regulation S-K, which imposes additional, more detailed requirements for non-GAAP measures included in documents filed with the Commission — among them a requirement to give equal or greater prominence to the comparable GAAP measure and to explain why management believes the non-GAAP measure is useful. The practical takeaway is that the GAAP figure is meant to be visible and primary, with the non-GAAP measure presented as a supplement that is explained and bridged, not as a substitute that stands alone.

The reason the rule centers on the reconciliation is that the adjustments are where the analytical work lives. A company can report a healthy adjusted EBITDA while its GAAP results show a loss; the gap between the two is the sum of the add-backs, and the reconciliation is what makes that gap legible. By requiring the most directly comparable GAAP measure to appear alongside, the rule prevents a non-GAAP figure from floating free of the audited accounts. For a reader, the reconciliation table is therefore the most informative part of a non-GAAP presentation — not the headline adjusted number, but the list of what was excluded to produce it.

How to read a reconciliation in a storage-company release

Reading a non-GAAP reconciliation well means starting from the GAAP figure and working up through the adjustments, asking what each add-back represents and whether it is genuinely non-recurring. Stock-based compensation, for example, is a recurring, real expense that many companies add back; treating the resulting adjusted figure as if those costs do not exist would overstate underlying profitability. Restructuring charges that recur every quarter raise the same question. Regulation G's framework — comparable GAAP measure plus reconciliation — exists precisely so a reader can perform this scrutiny: the rule guarantees the GAAP anchor and the bridge are present, and the analytical judgment about whether the adjustments are reasonable is left to the reader.

The framework matters most precisely in sectors where adjusted metrics carry the narrative. Many energy-storage and clean-technology companies report substantial GAAP losses while presenting adjusted figures that look closer to break-even, and the difference is built from a stack of add-backs the reconciliation is required to itemize. Because Regulation G guarantees the comparable GAAP measure appears alongside, and because Item 10(e) of Regulation S-K requires that GAAP measure to be given equal or greater prominence in filed documents, a reader is never supposed to encounter the adjusted number in isolation. When a company foregrounds adjusted EBITDA, the rule entitles you to find the GAAP loss it was derived from in the same disclosure, given at least equal prominence — and if it is hard to locate, that prominence requirement is itself the thing to scrutinize. The reconciliation table, in other words, is not a courtesy; it is the mechanism the SEC built to keep the audited result from disappearing behind the adjusted one.

The grounded definition is firm: a non-GAAP reconciliation is the SEC-required bridge from a non-GAAP measure to the most directly comparable GAAP measure, mandated by Regulation G whenever a company discloses a non-GAAP figure, and reinforced for filed documents by Item 10(e) of Regulation S-K. What the rule does not do is bless any particular adjustment as appropriate — it requires disclosure and reconciliation, not approval of the adjustments themselves. That is the correct boundary for a reader to hold: the rule guarantees you can see how a company got from its audited results to its preferred number, and it puts the burden on you to judge whether the path is fair. In a sector where adjusted metrics feature prominently in earnings communications, the reconciliation is the discipline that keeps the audited GAAP figure in view.