The options market priced about a 1% day for the S&P 500 last Thursday.
It fell 4.4%, four times that.
Against the volatility priced the day before, it was the biggest surprise since February 2007 and the third biggest since 1990.
Desk notes, November 2026
The desk notes of Sophos Alpha, an independent quantitative research desk. Daily market notes across many topics, including CTAs, risk parity, vol control and other systematic funds, hedge fund activity and investor sentiment, dealer gamma and liquidity, volatility and tail risk, in equities, rates, currencies and commodities.
November 2026
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Just when the market needed it most, liquidity at the top of the book evaporated.
Last Thursday, resting size in S&P 500 futures fell to $4.1mm, thinner than on 94% of sessions in the past two years.
At the same time, 28bn shares traded across US equities, more than on 99% of days.
The gap between the two was the 7th widest in two years, and only the Liberation Day week and late June were wider. This is the most vulnerable a market can get.
Read how systematic funds added to the fuel:
A third of the leverage in US levered ETFs is gone in five weeks.
Gross exposure fell from $520bn on October 6 to $349bn, the lowest since mid April, and assets from $202bn to $135bn.
That is $171bn less exposure for these funds to rebalance into the next big move.
CEO scandals hurt the stock for about a month.
Then the market stops caring.
After $NVDA's news, we built a “CEO scandal list”: every major company whose sitting CEO announced a divorce or got caught in an affair since 2000.
A CEO affair hurts the stock for about a month. Then the market stops caring.
After a volatility shock like last Thursday's, the Nasdaq 100 has tended to chop for a month before it recovers.
One month later NDX was up just 55% of the time. Three months later, 80% of the time and 5.9% on average. Six months later, 82% and 12.7%.
The Nasdaq lost $2.49 trillion in market value last Thursday.
The entire Nasdaq was worth $2.98 trillion at the end of 2003.
It was the biggest one day loss on record, and 3 of the 10 biggest have now come in the last three weeks.
Betting on lower volatility is the new betting on higher stocks.
Last Friday investors didn't chase calls on the S&P 500 or the Nasdaq 100, they chased puts on the VIX. The VIX put/call ratio closed at 1.49, the highest in two years and nearly 3 times its 0.51 average.
The Nasdaq 100 has had 12 trillion dollar days this year.
Before 2025 it had one.
Its biggest move in all of 2008 was $283 billion. Last Thursday it dropped $2.53 trillion, the largest one day loss on record.
Read our latest piece on how the mechanisms for this move were already in place.
Stress that stayed in single stocks all year finally hit the index last Thursday.
Everything traded as one.
S&P 500 3 month implied correlation jumped 8.8 points in a day, the biggest jump since Liberation Day, to its highest level since April.
Investors dropped their hedges after Wednesday's post midterm rally and got caught on Thursday.
VVIX, the volatility of the VIX, jumped 44.6 points, its second biggest day since 2006.
How that day unfolded, in our latest Institutional Monitor.
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A big rally followed straight by a big drop almost never happens near a record high.
The S&P 500 did it on Thursday, a day after the midterm rally. Since 1980, only four came this close to the top: twice in 1987, then 2014 and 2020.
Thursday's drop was the deepest of them all.
Thursday's fear spike came out of dead calm.
Only twice since 1990 has the VIX jumped further from under 20.
Going in, it sat below its one year average. Then the AI trade cracked after the midterms, and the Nasdaq 100 had its worst day since March 2020.
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Thursday Was the Biggest Put Day in Cboe History
The Nasdaq 100 had its worst day since March 2020, and the rush for protection topped even the April 2025 tariff panic. Index puts led the way.
Eight of the ten biggest put days came this year, three in the last three weeks.
Volatility did not just rise on 5 Nov, it overshot.
A day after investors sold their hedges, the VVIX posted its second largest jump on record and Nasdaq vol rose far more than the selloff explains.
A market caught without protection.
Semis just had their worst week against the S&P 500 since 2001.
Chips fell 12% on 5 Nov alone, their worst day since March 2020. The group that led this market higher is now leading it lower, and one green day does not undo a gap this wide.
We estimate about $155bn of forced systematic equity selling on 5 Nov.
Vol control funds were already selling into the 4 Nov rally. CTAs were caught off guard: they bought the bounce, then had to unwind most of it the next day.
Levered ETFs piled on at the close.
The AI trade just had its biggest one day drop since ChatGPT launched.
Memory and optical networks fell over 15%. The market is repricing the datacenter buildout, and the names that ran hardest on it are giving back the most.
A crowded trade is looking for the exit.
Investors took their hedges off the day before they needed them most.
4 Nov: our Volatility Stress Index posted one of its largest one day drops on record as protection was cashed in.
5 Nov: one of its largest jumps, straight to near maximum stress.
Never two moves this big back to back since 2011. The market got caught off guard.
Historically, when the VIX spikes, 12 month forward returns improve, because fear creates dislocations and better entry points.
At a VIX of 28 or higher, the S&P 500 was up a year later 84% of the time since 1990, with nearly double the average gain.
It closed at 28 yesterday.
Even the professionals got caught off guard yesterday.
Stock picking hedge funds had a 2 std dev down day. Tech funds lost over 4% and are now roughly flat for 2026, after being up about 24% before the summer AI selloff.
Only the quant stock pickers finished higher.
The S&P 500 fell 4.4% yesterday, its worst day since April 2025.
Out of nearly 25,000 sessions since 1928, it ranks 123rd worst, inside the worst 0.5% of all trading days. Since 2000, only 33 days were worse.
The VIX jumped 70% yesterday, its third biggest one day gain since 1990.
On 18 Oct we flagged that extreme short positioning by asset managers in VIX futures has coincided with strong VIX forward returns. https://substack.com/@sophosalpha/note/c-364243897
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Stocks and bond yields have moved together for two weeks straight, the strongest link since February.
For most of 2026 this chart was one negative block: every rate scare a hit to equities. That flipped in late October. The worry moved from rates to growth.
Where could the next financial crisis start?
Maybe in the safest market in the world.
Hedge funds now hold $3.9tn of gross Treasury exposure, 2.3x the end of 2022. Their repo borrowing, the short term loans that fund those positions, has nearly tripled to $3.4tn.
That is leverage stacked on government debt. If yields jump and lenders pull back, funds are forced to sell into a falling market. The UK saw a version of this in the 2022 LDI crisis, and the US with LTCM in 1998.
Both times policymakers stepped in fast. The positions are far bigger now.
Could the AI boom cause the next financial crisis?
Crises tend to need two things at once: a big run up in asset prices and a surge in borrowing. Stocks have the first. Real equity gains in the US and Japan over the last three years sit above the danger line.
Borrowing is the missing piece. US business credit has fallen almost 6 points of GDP over the same three years. Going into 2000 and 2007 it was rising 7 to 9 points.
So an AI correction is the clearer risk, not a crisis. That changes if companies start borrowing to keep building.
Where did the 2008 debt go?
To the government. In 2007, US government debt was 61% of GDP, third of the four big borrowers. Today it is 119%, the largest. Households went from 97% to 66%, and the financial sector from 143% to 85%.
Total debt is lower as a share of GDP than in 2007. What changed is who owes it.
That is a big reason there has been no crisis since: a government doesn't face a run the way a bank does. But every rescue loaded the sovereign balance sheet, and with interest costs rising, there is less room for the next one.
Why hasn't there been a banking crisis since 2008?
Part of the answer: banks hold less of the system than ever. Their share of US financial assets is 18%, the lowest since records start in 1945, down from 58% after the war and 23% at the end of 2008.
That matters because banks run on deposits that can leave overnight. A pension fund or a closed end private credit fund can't be emptied on demand, so the classic bank run has less to work with.
The risk didn't disappear. It moved outside the banks, where it is harder to see.
We warned two weeks ago: vol of vol was flashing a warning VIX hadn't confirmed yet.
VIX is up 69% today. Only two days since 1990 saw a bigger jump: 5 February 2018 and 18 December 2024. March 2020 never got there.
Vol of vol rose 38 points, beaten only 4 times since 2006.
We warned you since the weekend: systematic selling in equities is alive and vol control has the most room to sell.
Levered ETFs sell $48bn into today's close on the moves so far.
Vol control sold $22bn yesterday and a 2% lower close forces $23bn more.
What does a bank run look like in the bond market?
13 March 2023. Silicon Valley Bank had failed the Friday before, and the two year Treasury yield fell 57 basis points in a day, its biggest one day fall since the day after Black Monday in 1987. Even after 9/11 it moved less.
Then policymakers moved faster than the panic. Every SVB deposit was guaranteed, the Fed opened a new lending program, and its balance sheet grew $0.4tn in two weeks.
The run stopped at a handful of banks. That speed is a big part of why 2023 never became 2008.
Does a stock market crash mean a financial crisis?
Not on its own. The S&P 500 has had 12 bear markets from a record high since 1929, and four of them came and went without a recession: 1962, 1966, 1987 and 2022.
A selloff becomes a crisis when the system amplifies it.
Leverage, bank runs, fire sales and margin calls carry the shock into the economy. Without them, prices fall hard and the damage stays in the market. With them, a small trigger cascades, as in 1929 and 2008.
The VIX just had its sharpest one day collapse since the April 2025 tariff shock, down a fifth in a session, more than on any day of the US Iran war.
Every dip this year brought a bid for protection. Wednesday the VIX fell twice what a rally that size usually costs. Hedges off.
Does the S&P 500 go higher after midterms?
22 of the last 24 times it did, up 13.7% at the median a year later. Every one since 1946 ended higher, 20 of 20. The misses: 1930 and 1938.
History says higher. With the index this concentrated, a 22nd straight hangs on a few stocks.
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What happens to stocks when the 10 year yield surges?
After 2022, rises of 90 to 170bp came with S&P 500 drops of 5 to 10%, except once, when stocks climbed. The 300bp jump of 2022 cost 25%.
This year yields hit 5.31%. The worst S&P drop along the way was 7.8%.
November is the Russell 2000's best month.
Small caps rose in 9 of the last 10 Novembers, averaging 5.6%. Going back to 1979, it is still the top month on average.
October closed higher this year. After an up October, November rose 20 of 27 times.
Do midterms cause selloffs?
Rarely the main one.
The big S&P 500 drops near midterms since the GFC, 20% in 2018 and 25% in 2022, came with Fed, tariff and inflation shocks. The vote was a contributor at most.
Into this week: 3% off the high. Not even a garden variety pullback.
Do stocks rally after the midterms?
Since 1974 the S&P 500 was higher by late February in 11 of 13 midterm years, with the typical gain near 6% from the Election Day close.
This year the market skipped the usual fall slump, so it heads in from strength, not a washout.
Tech stocks are down $5 trillion of market cap over the last 3 weeks, and yet the majority of the S&P is up over the last month.
Breadth is turning fast. In early October the market was its narrowest since 2000. The last 3 weeks brought the sharpest broadening since mid 2024.
What happens to volatility when the midterms are over?
It usually stays high. In midterm years, S&P 500 volatility peaks in October, and in 2 of 3 cycles it ran above normal through January.
Even December, normally the calmest month, has run hot after the vote.
Health Care is up 10% in a month while the S&P 500 fell 2.6%.
A lead that wide has shown up only a handful of times since 1999.
Money is moving from offense to defense. 9 of 11 sectors rose over the month. Only Tech and Communication fell.
Oil has nearly doubled this year, and October poured more fuel on it.
Tech took the hit. The Nasdaq had its worst month since early 2025 and Korea got crushed. Bonds finally caught a bid as yields backed off their highest levels since 2002.
Gold and silver kept bleeding.
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CTAs have cut equity exposure from 61% in mid August to 11%, the 9th percentile of the past year.
Vol control funds are where the room to sell is now.
They sold an estimated ~$150bn over the last few days, yet their exposure still sits in the top 30% of the year. Another 2% down day would force $100 to 120bn more.
VIX closed at its highest level since June yesterday, and single stock vol at its highest since early August.
Index and single name vol both repriced higher after the last few days of selling. VIX is back at the bottom of its Iran war range, and vol of vol is at its highest since April.
The options market is paying up for protection into the midterms, priced as the largest one day S&P 500 move left this year at just over 1%.
The average stock just beat the S&P 500 by the widest margin since 2009.
For years the biggest names carried the index. In October the rest of the market left them behind.
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You can't stop the machines once volatility picks up.
Fundamentals are not part of these models, and neither are headlines or what someone said on a CNBC panel overnight.
Systematic funds WILL deleverage as realised volatility rises, and they keep selling into bounces. That is why the market can feel heavy.
Based on our numbers, levered ETFs sold $38.4bn into Friday's close. Semis ($18.6bn) and Tech ($11.2bn) were most of it.
We cover what a persistent high vol environment looks like in our latest piece.
Options are pricing the next 12 months as one of the least correlated years for S&P 500 stocks in two decades.
Under the surface single stocks keep swinging hard while the index stays calm. The options market expects that split to carry into 2027.
Hedge funds have been piling into Russell 2000 longs since September, but they kept their shorts on.
That short pile is still one of the biggest in almost a decade, the squeeze risk we flagged on Friday. Small caps beat the Nasdaq last week while tech sold off on earnings.
Apple broke away from the Nasdaq 100 this fall.
Their 3 month correlation turned negative for the first time ever.
It reports earnings today with that link only just back above zero.
November has been one of the best months for stocks over the last 20 years, positive on average for every index here.
Small caps lead it. The Russell 2000 has done better in November than in any other month, and finished higher in three of every four Novembers.
Stocks don't need a recession to crash.
Three of the last four S&P 500 bear markets came without one: the 2018 trade war, 2022 inflation and the 2025 tariff selloff.
Since 1955 it has happened 9 times.
Downside buying in the index and semis sent VVIX to the highest level since Iran/US started on Friday before cooling off.
In our latest piece we share an inside look of what will happen to the market if we enter a persistent volatility regime.
Every one of the 100 busiest days of all time for US options came in 2025 or 2026.
Friday traded close to 100 million contracts, near the very top of that list. Index options just had their second biggest day ever, two weeks after their biggest.
Nasdaq 100 vol was crushed into Thursday, then Friday snapped it back above where the week started.
That jump ranks among the 10 biggest one day rises of the past year, and vol now sits higher than on almost 9 in 10 days of it.
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The equal weight S&P 500 now has just a 64% correlation to the S&P 500.
Its long run norm is 98%.
That is lower than 99% of sessions since 2007, and the record low came only in September at 57%.
The market is so fixated on AI that stocks have stopped moving with the index.
Speculators have now sold gold for 5 straight weeks, and the selling is speeding up.
Their net long is down 35% from a record $131bn in late August to $85bn. Nearly $8bn went out in the latest week alone, the biggest of the run, and gold fell another 4.3% into month end.
Two weeks ago we warned: extreme short positioning by asset managers in VIX futures has coincided with strong VIX forward returns.
Since their record short, VIX has climbed as much as 59%, with its biggest intraday jump since April 2025 on Friday.
The S&P 500 fell 0.30% on 29 October despite 81% of its stocks closing HIGHER.
No down day since 1997 has had more stocks rising.
The market is so fixated on AI that the index and its stocks have stopped moving together.
Friday's S&P 500 move was 1.7 times what the VIX was pricing going into the day.
That happens about once every 24 sessions.
Only two other sessions since the Iran strikes beat the VIX by as much.
