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Working Paper

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Loss limitations are an ugly but inevitable feature of any realization-based income tax. In essence, because the system mismeasures gains, it also has to mismeasure losses. Otherwise, the timing option inherent in the realization rule would allow taxpayers to defer gains (thereby reducing the tax's present value) while accelerating losses (thereby preserving the deduction's present value).

The wash sale regime of Section 1091 is one of our system's most important brakes on the timing option. Yet it is only a slight exaggeration to say that compliance with the regime is voluntary for very wealthy taxpayers – or, at least, for those who are willing to take aggressive positions. In response, this Article flags seven glitches in the regime that, at least arguably, permit perfect end runs. As used here, this phrase refers to strategies in which taxpayers can deduct losses while effecting virtually no change in their economic position. The essential point is that, if we are going to have a wash sale regime, these end runs should not be allowed.

This Article also takes a more controversial position: Losses should still be deferred – even when taxpayers make meaningful changes in their economic position – as long as they keep material elements of their old return. The policy goal here is to ensure that, on average, taxpayers expect losses to be deferred as long as gains. This Article proposes concrete modifications in the regime to implement this goal, while also offering a caveat: The case for a strong wash sale regime is less strong if the regime can never be tough enough to stop loss harvesting. If so, other constraints on the timing option may be preferable, including accelerated timing for gains or a broader capital loss regime.


Law | Law and Economics | Tax Law


Center for Law and Economic Studies


Center on Global Governance