BofA analysis of CTA positioning and systematic selling risk
Bank of America (BofA) analysts note that the recent decline in U.S. equity prices has prompted Commodity Trading Advisors (CTAs) to derisk and unwind long equity positions, and they caution that a further ~3% decline in the S&P 500 could unleash additional systematic selling. After the latest market pull‑back, many CTAs trimmed bullish long exposure yet still hold a net positive stance on equities.
The analysts attribute the reduction in S&P 500 longs to more aggressive stop‑loss frameworks, while Nasdaq‑100 (NDX) positioning fell further among models employing medium‑tier stop thresholds. Within the Nasdaq‑100, the remaining long base is now concentrated among the least risk‑sensitive models, whereas S&P positioning reflects a mix of medium‑ and low‑sensitivity longs.
Despite the pull‑back, the SG CTA Index closed positive on the Thursday rebound, indicating that CTAs continue to retain long exposure to major U.S. equity benchmarks. BofA adds that, after accounting for Friday’s rebound, another ~3% drop in the S&P 500 and ~5% decline in the Nasdaq‑100 could trigger further systematic selling.
CTA exposure remains elevated in the Russell 2000 and Nikkei, and, as price trends strengthen, Europe is expected to see incremental buying. The largest CTA exposure is concentrated in shorter‑duration futures, while CTA positioning in U.S. Treasury futures stays short. Declining yields this week have moved buy‑to‑cover triggers closer, and BofA suggests that a continued yield decline—potentially spurred by a dovish Federal Reserve decision next week—could prompt trend‑follower short covering.
Commodity trends show that oil prices have fallen in three of the last four weeks, putting CTA longs to the test; the most risk‑averse CTAs may have already been stopped out, with additional stops expected if declines persist. Similarly, CTAs could be selling gold as trends weaken; the fastest trend followers have been short gold for the past couple of months, while medium‑ and long‑term followers are seeing their long positions eroded.
Regarding options, after the market shock on June 5, S&P 500 (SPX) gamma became more muted, though it still retains long exposure. Prior to the shock, SPX option gamma had reached the 99th percentile, but since June 11 it has normalized to $1 billion, placing it at the 28th percentile level since 2014. Most expiries over the next month are contributing positive SPX gamma at current spot levels, while longer‑dated options remain a largely offsetting source of short gamma. BofA projects that SPX gamma could stay positive within the 7,320‑7,625 range unless new flows emerge next week.