The Invisible Balance Sheet: Can Intraday Financial Markets Detect Corporate Deterioration Before Accounting Disclosures?

Do one-minute financial markets see a firm's forthcoming accounting deterioration before daily markets do? This paper builds a strictly point-in-time panel of 3,796 U.S. listed firms and 102,522 firm-quarters (2013–2026) from 6.7 billion raw one-minute bars and quarterly statements with filing and release dates, and forecasts an adverse operating-income surprise, defined against a seasonal random walk with drift and never against prices, twenty trading days before the earnings release. Holding the information set, the universe, the horizon and the model capacity fixed, the same families of realized measures, volume composition and market co-movement computed from 30-minute, 5-minute and 1-minute bars are added to a benchmark that already contains point-in-time fundamentals and daily OHLCV, with an identical 24-trial tuning budget for every information set and twelve leakage guards implemented as unit tests.Fundamentals explain most of the predictable variation (log loss from 0.6282 at the base rate to 0.4937 with gradient-boosted trees, AUC 0.797), daily market data add a clear increment (−0.0068 [−0.0095, −0.0042], AUC 0.803), and one-minute data add nothing: the paired out-of-sample change in log loss on the untouched 2021–2026 test period of 53,667 firm-quarters is +0.0013 [−0.0013, +0.0041] with logistic regression and +0.0016 [+0.0010, +0.0023] with trees, intervals that exclude any gain at all with trees and any gain larger than a fifth of the daily increment with logistic regression, against a pre-registered minimum detectable difference of 0.0025. The 30-minute and 5-minute families behave identically (+0.0017 and +0.0021 with trees), and concatenating all three resolutions is worse still (+0.0030).The null survives five horizons from forty days to one day before the release (rank correlation between gain and proximity −0.50, p = 0.39), five accounting targets, a symmetric volatility placebo, firms never seen in training (+0.0018 on held-out firms), every annual refit and every pre-specified subgroup. The small information content of the incremental one-minute signal is concentrated in large, levered firms rather than in neglected ones (panel coefficient −0.0129, t = −1.76, against −0.0765, t = −32.22, for the daily benchmark signal), is already impounded in prices at the cutoff (announcement-window abnormal return unrelated to the signal, t = 0.01), and has no economic value in factor-adjusted portfolio sorts (FF5+momentum long–short alpha −0.59% per month, t = −1.85, gross; −0.62% net of 20 bps per side). The accounting panel is conditioned on firms listed in November 2026, a survivorship caveat the paper documents rather than resolves.UQO Working Paper No. 39, version 1.0 (November 2026), 34 pages. Département des sciences administratives, Université du Québec en Outaouais. JEL: G14, G12, G17, M41, C53, C58. Also archived on Zenodo: https://doi.org/10.5281/zenodo.23933468 and at https://www.spboucher.ai/research/wp39.