Tax Alpha Insider

Tax Alpha Insider

Yes, really, $1 trillion in box-spread AUM

This number is easy to ballpark... and could be an underestimate

Brent Sullivan's avatar
Brent Sullivan
Nov 20, 2025
∙ Paid

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Yes, really, $1 trillion in box-spread AUM

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$1 trillion is a lot, but the market may be larger

A month ago, I wrote 5 ways to intuit the box spread and followed up with $1 trillion box-spread AUM is up for grabs.

The only thing that’s changed since then is that more vendors have popped onto my radar.

I have more box spread work on the way, including a close look at SyntheticFi’s mortgage product, but that will have to wait until Jan 2026.

Several folks wanted to know more about the $1 trillion figure, so below is a breakdown using Fed and FINRA data.

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