One hesitates to write history as it happens, or to draw policy lessons from current events. The conference took place in May 2008 - after the government-assisted takeover of Bear Stearns but before a capital market downturn fueled a system-wide liquidity crisis, with successive insolvencies at IndyMac, Fannie Mae, Freddie Mac, Lehman, AIG, WaMu, and, as I write, Citigroup. But it would be odd to comment on capital market regulation without mentioning the events of the last three months. I am first to acknowledge that anything I might have written in May would not have foreseen the crisis or linked capital market regulation to financial institutions, which in the US have been conventionally treated as discrete in discourse and institutions (e.g., U.S. Treasury 2008; Leuz and Wysocki 2008).

ABSTRACT We examine management discretion to decide when and how much to write down an asset, in a unique case where a tracking stock provides an observable market value for the asset. We find that, despite market evidence that Inco Ltd.'s financial statements substantially overvalued the Voisey's Bay nickel mine throughout 1997 to 2000, management chose not to write down the mine until 2002. Inco management used an independent fairness opinion to justify its December 2000 redemption of the tracking stock at 25% of its initial value, indicating almost surely that Inco management was aware of the generally accepted accounting principles (GAAP) impairment. This case illustrates that GAAP's reliance on undiscounted cash flows for impairment decisions allows huge unrecorded disparities between book and market value. The management discretion exercised in this case provides a concrete example of the subjectivity inherent in fair valuation.