One consequence of the shift to fair value measurement is the emergence of voluntary disclosures in audited financial
statements that question the reliability of mandated fair value information. We refer to these disclosures as reliability
disavowals (hereafter, disavowals). We examine disavowals of employee stock option compensation (SOC) estimates
disclosed under Statement of Financial Accounting Standard 123 (SFAS 123). We test whether they are informative
regarding reliability issues or are opportunistic. SFAS 123 encouraged firms to recognize a fair value estimate of SOC
expense, but most firms elected the intrinsic value method and provided a required pro forma footnote disclosure of the
associated with four factors—short firm trading history, historical volatility that is itself volatile, lack of exchange-traded
options, and large differences between historical volatility and independent estimates of future volatility—indicative of
volatility estimates being unreliable. In contrast, we find modest evidence of opportunism. None of the three opportunism
proxies are associated positively with the disavowal decision in the initial period, but one, abnormal compensation, is
positively associated in 2001–2005.
Our second set of tests examines forecast bias in managers’ volatility estimates. We find no evidence of downward bias
in disavowal managers’ mean volatility estimates relative to either realized volatility or three ex ante volatility benchmarks