What happened in markets overnight?
The US military struck Iranian rocket launchers on Larak Island in the Strait of Hormuz on Sunday, the first American action in the region in roughly a month, after CENTCOM said the Revolutionary Guard was loading the launchers with sea mines. Oil jumped in response: Brent crude rose to $90.69 a barrel, up nearly 3% from the prior session, while WTI traded near $86. US equity futures moved the other way but barely: S&P 500 and Dow futures were down about 0.1% as of 4 a.m. ET Monday, with Nasdaq futures roughly flat.
Why aren't energy stocks moving more with oil?
Energy majors did move, just not by much relative to the size of the oil spike, and the sector-wide picture is muted once refiners, drillers and integrated names get averaged together. Halliburton was up more than 2.5% in premarket trading and Chevron gained about 2%, with Valero, Occidental and Exxon posting smaller gains. On a broader industry basis tracked on OpticAlpha's sector heat map, the combined Oil & Gas grouping was up only about 0.2% at the same time, a much smaller move than the headline names suggest.
A supply-shock headline typically sends energy stocks up in lockstep with the commodity. That isn't happening cleanly here. Traders have reportedly started treating this as more of a sanctions and posturing story than an actual threat to physical crude flows, with Goldman Sachs estimating Persian Gulf exports have recovered to 15-16 million barrels a day, well above the crisis low but still short of the pre-conflict 22-24 million.
What's actually driving today's sell-off?
The sharpest red on the board this morning isn't energy-adjacent at all. It's semiconductors, which are down between roughly 2.9% and 4.0% across two separate chip-industry groupings on the same sector heat map, a far bigger move than anything tied directly to the Iran news.
That selling is a continuation of last week's chip unwind, not a new event. Marvell Technology fell more than 10% on Friday after fiscal second-quarter results beat estimates but softer fiscal 2028 revenue guidance and a lack of detail on its Google chip deal disappointed investors, even as management raised 2027 guidance to $12 billion and 2028 guidance to $18 billion. Applied Materials dropped roughly 3.6% the same session amid broader profit-taking across chip-equipment names.
Part of why "semiconductors" can drop several percent as a group on names most traders don't hold: concentration. The VanEck Semiconductor ETF carries roughly 17.6% of its weight in Nvidia and 9.3% in Taiwan Semiconductor, so a two-stock wobble reads as a sector-wide move.
What happened to PayPal, and why did the stock drop 12%?
PayPal fell about 12.7% after Bloomberg reported that a buyout consortium led by Stripe and private-equity firm Advent International had abandoned its pursuit of the company. The group had floated an offer of $60.50 a share for a deal valued near $53 billion, but talks over a higher price broke down. That earlier takeover chatter had already added roughly 30% to PayPal's stock before the deal talk collapsed. With the buyout off the table, PayPal returns to executing its turnaround on its own, competing against Apple Pay and Google's payment products without a deal premium underneath the stock.
Where does volatility sit through all of this?
Not high. The VIX closed Friday at 14.43, down 0.55% on the day and still near its low for the year, a reading that reflects calm at the index level even as individual sectors moved several percent in opposite directions underneath it. A quiet VIX print is measuring the S&P 500's day-to-day swings, not what is happening inside chips, energy or single names like PayPal.
What should traders watch this week?
Whether chip names stabilize above Friday's lows matters more than the oil headline does for near-term direction, since the Iran story has so far failed to translate into a clean, broad-based rotation into energy. If crude keeps climbing without a matching move in energy equities, that is itself information: the market is pricing this as a geopolitical and sanctions story rather than a genuine threat to physical supply. September brings a heavier data and earnings calendar, including Tuesday's ISM Manufacturing PMI and a run of chip-adjacent earnings later in the week, both of which will test whether this divergence holds or resolves.
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