Fidelity's Timmer: Stock Selloff Tightened Bitcoin's Link to Equities

Jurrien Timmer at Fidelity notes that Bitcoin (BTC) became more closely tied to the S&P 500 last week as other asset prices moved in lockstep. A portfolio of equities stripped of artificial intelligence (AI) stocks saw its correlation jump from 10% to 40% over the course of the week.

Assets meant to diversify away from equities should move in the opposite direction, so a strengthening correlation weakens that benefit for Bitcoin holders. Timmer, who serves as Fidelity's director of global macro, shared a 50-day correlation chart on X with data current through Nov. 8.

What Drove Bitcoin Correlation Higher Last Week?

The S&P 500 declined 4.4% on Thursday, Nov. 5, and the Nasdaq 100 lost 6.4%. Those drops were attributed to expectations that Democrats, having won control of Congress, would impose tighter rules on AI.

Timmer laid out the pattern on X.

“When markets fall hard and fast enough, correlations often converge, and we can see below that this happened last week as well.

Jurrien Timmer, Director of Global Macro, Fidelity Management & Research Company, on X

When markets fall hard and fast enough, correlations often converge, and we can see below that this happened last week as well. Earlier last week the ex-AI basket was only 10% correlated to the S&P 500 index, but by the end of the week it was 40%. The same applies to the S&P 500… pic.twitter.com/VvIdp7eZ51

— Jurrien Timmer (@TimmerFidelity) November 11, 2026

The post added that the equal-weight S&P 500, Real Estate Investment Trusts (REITs) and Bitcoin also converged. Correlation tracks the degree to which two assets move in tandem, with 100% indicating a perfect match.

Bitcoin itself fell 5.4% on that Thursday, a steeper drop than the S&P 500, while Wall Street's fear gauge surged nearly 70%.

Which Diversifiers Still Hold Up After the Rout?

The chart maps roughly 20 assets against the S&P 500 and long-term Treasuries, drawing on data from Bloomberg and Haver Analytics. Fidelity's December outlook listed Bitcoin, gold and commodities among Timmer's go-to diversifiers.

Nonetheless, the U.S. dollar and the Bloomberg Commodity Index remain at or below zero correlation with the S&P 500. Commodity Trading Advisors (CTAs), which follow price trends, show a similar pattern.

By contrast, Bitcoin behaved more like gold than the Nasdaq in August. Grayscale research pegged its 90-day correlation with the Nasdaq 100 at roughly 33%, down from over 60%.

The episode demonstrates that a selloff driven by chip stocks can affect assets with little direct AI exposure, including Bitcoin and REITs.