In appraisal, across the majority of states–and those countries we have reviewed–the main question is the “fair value” of a petitioner’s shares. Some courts and commentators have mixed “fair value” with a similar but economically distinct term: “fair market value.” But even if everyone agrees on what fair value means, that does not mean the law is uniform as to when fair value is being calculated. Consider: Delaware law tasks the court with determining the fair value of the shares as of the merger date. At the other end of the spectrum, California law requires a court to determine the fair value of shares immediately prior to the announcement of the merger. Two states’ laws thus deal with certain eventualities in very different ways. What if the deal takes a long time to close? For California, this makes no difference; the “interim events” between announcement and closing do not come into the analysis. But for Delaware, interim events can have great significance–just because management has struck a deal (including a price) months, sometimes many months, before closing does not mean that that price reflects the value of the company at closing. As an example, imagine an early-stage biotech company or a speculative gold miner. Deal price may be set and a shareholder vote taken; then the company receives FDA approval or a claim pans out, and at closing, the buyer receives the benefit of the increased value while shareholders do not. In larger deals, where numerous regulatory hurdles need to be cleared, the difference in the date of the fair value measure can mean the difference in measuring during a positive or a negative business cycle. So in any appraisal action, the “when” of fair value matters.