(Zhang Xiaotian/Getty Images)

S&P 500 goes nowhere, Nasdaq 100 hits another record, small-caps tumble

Warner Bros. Discovery led gains for the second day in a row, and only three S&P 500 sector ETFs finished in the green.

9/12/25 4:43PM

The good: the Nasdaq 100 rose 0.4% to close at a record high for three consecutive sessions, the first time that’s happened since late July.

The meh: the S&P 500 finished down less than 0.1%.

And the ugly: the Russell 2000 sank 1%.

Only three S&P 500 sector ETFs finished in the green: communication services, consumer discretionary, and utilities. Healthcare was the worst performer.

Warner Bros. Discovery led gains for the second day in a row, jumping 16.8% after The Wall Street Journal reported that Paramount Skydance is preparing a takeover bid for the media giant. Declines were led by Moderna, which sank 7.4% after The Washington Post reported that the Trump administration plans to link the coronavirus vaccine to 25 child deaths. Shares of Pfizer were also down 3.9%. Elsewhere…

Tesla shares leapt 7.4% following reports that the EV maker now has a permit to test its autonomous vehicles in Nevada.

Microsoft rose 1.8% after the tech giant and OpenAI announced a “non-binding memorandum of understanding” for their renegotiated $13 billion partnership, which had been a source of recent tension between the two companies.

Super Micro Computer jumped 2.4% after the company announced it has started shipping “Plug-and-Play (PnP)-ready” racks powered by Nvidia’s new Blackwell Ultra chip.

Six Flags popped 7.8% after the amusement park operator reported a rebound in attendance and early season pass sales heading into the fall.

Restoration Hardware fell 4.7% after the luxury furniture brand missed Q2 estimates and tightened its full-year outlook, as tariffs and housing market softness squeezed margins.

Rivian shares dropped 3.7% after the EV maker recalled 24,214 vehicles due to a software issue.

Tasha Matsumoto

14h

Stocks eke out gains on hopes for a path forward for reopening the Strait of Hormuz

Stocks rebounded on news that Iran is drafting a protocol with Oman to “monitor transit” through the crucial Strait of Hormuz.

Matt Phillips16h

AI server cluster maker Penguin Solutions takes flight

Small-cap AI server cluster maker Penguin Solutions surged Thursday after posting better-than-expected Q2 revenue and profit numbers Wednesday after the close, along with an increase in full-year sales and profit guidance.

The company, which was known as Smart Global Holdings until July 2024, has positioned itself as a provider of “end-to-end AI infrastructure solutions.”

Its Advanced Computing division designs and sells computers, cabling, and cooling systems, the server racks and clusters of racks AI data centers need. Its other main division sells flash and DRAM memory products.

It’s a pretty small company, with a fully diluted market cap of just over $1 billion and roughly 2,900 employees, according to FactSet.

The stock is volatile. Penguin dove during last year’s tariff tantrum that followed “Liberation Day” in April. Then it turned tail and doubled through early October amid a surge of call options activity, which tends to reflect retail interest. From the October peak, it then plunged by about 50%, before Thursday’s renaissance.

For what it’s worth, call options activity in Penguin is pretty busy today, too — relatively speaking — with roughly 2,625 traded as of 1:15 p.m. ET. That’s the most since early January, when the company last reported quarterly numbers. The average volume over the previous 25 trading sessions is about 325 calls a day, FactSet data shows.

Penguin Solutions Stock Takes Off On AI Bolstered Outlook

The company, which was known as Smart Global Holdings until July 2024, has positioned itself as a provider of “end-to-end AI infrastructure solutions.”

It’s a pretty small company, with a fully diluted market cap of just over $1 billion and roughly 2,900 employees, according to FactSet.

Luke Kawa19h

Momentum returns to optics stocks as the release valve for AI optimism

Potentially imminent end to the war? Buy optics stocks.

Maybe not? Buy optics stocks anyway.

Effectively all the juice left in the AI trade is coming from optics (and memory) stocks. And the latter group is taking a bit of a breather today while the former continues to surge.

Shares of Ciena Corp., Lumentum, and Coherent are building on recent big gains and among the biggest gainers in the S&P 500 near midday, while Applied Optoelectronics is also surging on Thursday.

These companies all provide solutions that help information move around in data centers, and thus are key beneficiaries of the aggressive capex plans of hyperscalers. Nvidia has invested $2 billion apiece in Coherent and Lumentum in deals that also include purchase commitments.

Matt Phillips19h

Space stocks rip during a topsy-turvy day for the equity market

Satellite-services-from-space stocks surged Thursday after reports that Amazon is in talks to buy Globalstar, which provides voice and connectivity services from its satellite network. It also can’t hurt that the general mood around space is ebullient, following the successful launch of Artemis II on Thursday.

Planet Labs and ViaSat also soared on the news.

The gains for EchoStar — seen as a backdoor play at pre-IPO SpaceX exposure — and Rocket Lab were more muted, perhaps because a deep-pocketed competitor like Jeff Bezos getting serious about space services could complicate the plans of the two largest commercial space launch companies.

Rocket Lab and SpaceX see launch services as key to their aspirations of being major providers of voice and data services from low-Earth orbit satellites.

Tesla CEO Elon Musk’s SpaceX is the dominant provider of such services, and the early rumors on the company’s planned IPO — expected to be the largest ever — suggest the market is very excited about the prospects for the industry.

Elsewhere in the space stock world, Intuitive Machines — a maker of space infrastructure that provides services to NASA for lunar missions — also rose.

Globalstar surges after FT reports that Amazon is in talks to buy the satellite group

Rocket Lab and SpaceX see launch services as key to their aspirations of being major providers of voice and data services from low-Earth orbit satellites.

Elsewhere in the space stock world, Intuitive Machines — a maker of space infrastructure that provides services to NASA for lunar missions — also rose.

Hyunsoo Rim, David Crowther

Can Sandisk do the double?

20h

The S&P 500 just had its worst quarter in years. Here are the biggest winners and losers.

Sandisk and energy stocks soared while software names sank amid a broad sell-off in tech stocks.

Balancing balls of different sizes on pink seesaws creating equilibrium