• Citadel Securities strategist Scott Rubner expects equity market conditions to improve in October as quarter-end selling pressure fades and historically favorable midterm-election seasonality kicks in.
  • Corporate buybacks are set to return around October 13, with more than half of S&P 500 companies expected to reopen repurchase windows by November 1.
  • Rubner’s thesis rests on low investor positioning and negative sentiment, which could amplify a rally if prices begin to rise.

A Tactical Turn

Citadel Securities’ Scott Rubner is telling clients that the technical backdrop for U.S. equities is about to get a lot less hostile. In a note circulated this week, the firm’s head of equity and equity-derivatives strategy argued that the temporary headwinds that have weighed on stocks in late September—pension rebalancing, tax-loss selling, and the pre-earnings pause in corporate repurchases—are set to fade in October, potentially creating a more favorable supply-demand balance.

Rubner, who joined Citadel Securities in 2025 after stints at Goldman Sachs (GS) and Bank of America (BAC), had warned in early September that corporate buyback blackouts would accelerate around September 12, with quarter-end pension rebalancing and a large options expiration event amplifying volatility. By mid-to-late September, his tone had turned more constructive. He characterized any residual weakness as a re-entry opportunity rather than the start of a new bear market.

The corporate demand component is central to his thesis. According to reports summarizing the note, about 61% of S&P 500 market-cap weight was in pre-earnings blackout by September 30. More than half is expected to return to an open repurchase window before November 1, and almost all by roughly November 8. That means “around October 13” should be read as the beginning of a reopening process, not a single market-wide switch, Rubner said.

“The supply-demand balance should turn more favorable from October,” Rubner wrote, according to people familiar with the matter.

Buybacks and Seasonality

Corporate repurchases represent a persistent source of equity demand. Current estimates cited in market reporting put expected global buybacks at about $1.7 trillion in 2026, including roughly $1.3 trillion from U.S. companies. But announced authorizations are not the same as executed purchases; companies can slow or suspend activity if cash flows weaken or valuations rise.

Still, the return of buybacks is a welcome prospect for a market that has been starved of positive catalysts. The S&P 500 has struggled to gain traction in recent weeks, with an AI-led pullback in large technology shares and crowded positioning weighing on sentiment. Rubner reportedly expects that sector to stabilize early if the October recovery develops.

Seasonality also favors the bulls. Historically, October and November have been among the stronger months in midterm-election years. One compilation found October positive 71% of the time with an average 3.0% gain, and the November-to-following-June period positive in all 21 cycles since 1942. Citadel Securities’ own commentary has highlighted a seasonal late-October turning point: on average, October 26 is the fourth-quarter low for the S&P 500 and October 27 for the Nasdaq-100, after which the historically strongest seasonal stretch begins.

That record is descriptive, not causal proof. Elections can affect expectations around taxation, spending, regulation, and tariffs, but markets respond to actual policy outcomes, economic data, and valuations.

Positioning and Sentiment

Rubner’s bullish case requires more than just calendar effects. He argues that investor positioning remains low and sentiment negative, which could amplify a rally if prices begin to rise. Short covering and performance-chasing can accelerate an upward move when investors are underinvested.

“The setup is better,” Rubner said, according to the reports. “Positioning is low, sentiment is negative, and the flow backdrop should improve.”

But the same low positioning can also reflect legitimate macro concerns. Interest-rate expectations, inflation releases, labor data, corporate earnings guidance, oil prices, trade policy, and geopolitical shocks can overpower calendar effects. And research has found no consistently strong evidence that earnings-related buyback blackouts alone cause worse broad-market performance.

The practical implication is to separate seasonality from investment thesis. October’s historical pattern and returning buybacks may be useful context for risk management, but they are not substitutes for diversification, time horizon, and fundamental analysis.

Citadel Securities declined to comment on the note. A spokesperson for the firm did not respond to a request for comment on Rubner’s specific views.

Correction: An earlier version of this article misstated the percentage of S&P 500 market-cap weight in pre-earnings blackout by September 30. It was 61%, not 66%.