Marvell Raised Its Outlook $1.5 Billion. The Stock Still Fell.

Marvell Technology raised its fiscal 2028 revenue outlook by $1.5 billion in late August — and its shares still fell 8% in premarket trading the next day, to $223.10.

The drop tells the story of a stock priced for perfection and a payoff that keeps moving further out. Marvell (MRVL) has fallen 16.4% over the past three months, before dividends, while the S&P 500 returned 4.2% with dividends reinvested over the same stretch.

The stock has since recovered to $258.83, above the $241.45 close before the results. But the episode laid bare the tension at the heart of the Marvell bull case: a richly valued company whose biggest catalyst sits in fiscal 2029 and beyond.

What Buyers Are Paying

Marvell trades at 88.0 times its earnings over the past twelve months. The S&P 500 trades at 22.5 times. Investors are paying almost four times as much per dollar of yearly profit for Marvell as for the average large-cap company.

A price-to-earnings ratio that high only holds up if the business keeps growing fast. So far, it has. Marvell's revenue has grown 21% a year on average over the past three years. The S&P 500 managed 5.8% a year.

Most of Marvell's revenue now comes from chips for data centers, where AI demand keeps rising, management said. The company expects revenue to grow about 45% in fiscal 2027 and roughly 50% in fiscal 2028 — an acceleration, not a slowdown.

Why the Stock Fell on Good News

The late-August report lifted Marvell's fiscal 2028 revenue outlook to about $18 billion, up $1.5 billion from what management expected just one quarter earlier. Reuters reported that worries about when revenue from Marvell's AI chip deal with a large customer would arrive overshadowed the strong results.

That deal is the main attraction for shareholders. Management described the customer as one of the largest adopters of custom silicon. The expanded agreement covers programs already running, new design wins and potential future programs.

The catch is timing. Asked about the deal's size, management said most of it is already reflected in the fiscal 2028 outlook, and that because of this, the big impact would come in fiscal 2029 and beyond. Management also declined to put a figure on its fiscal 2029 custom chip revenue.

So a buyer today pays 88.0 times past profit while waiting for that big impact to arrive.

What Comes Next

The next scheduled event is Marvell's Investor Day on October 6. Management said it will give a deeper look at the drivers of its longer-term growth there. It also pointed to that day when it declined to size its fiscal 2029 custom chip revenue.

That leaves October 6 as the date when investors will learn whether the premium multiple is justified — or whether the wait for the custom-silicon windfall stretches out even further.