Marvell Technology shares closed at $218.34 on 29 October 2026, down 13.24%, the day after Bloomberg reported that Marvell is in advanced talks to buy data center optics maker Lumentum, according to people familiar with the matter. Lumentum closed up 0.61% at $919.53.
By our arithmetic, using the share counts on the companies’ latest filings, Marvell lost about $29.2 billion of market value in the session, equal to about 35% of Lumentum’s roughly $82.5 billion value at the close.
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The key insight: By our arithmetic, Marvell lost about $29.2 billion of market value on 29 October, equal to about 35% of Lumentum’s roughly $82.5 billion value, the day after Bloomberg reported the two are in advanced talks.
Marvell fell $33.31, from a $251.65 close on 28 October, according to Nasdaq closing prices via Yahoo Finance. About 41.8 million Marvell shares traded, by our arithmetic about 2.6 times the 16.3 million the day before.
The Motley Fool wrote that the stock “fell after reports surfaced that the company was in advanced talks to buy Lumentum Holdings, as investors weigh financing and integration risks”. It described the deal as reportedly all-stock.
Lumentum traded at $965, up 6%, in morning trading, 24/7 Wall St. reported, before closing up 0.61%. Coherent closed at $237.22.
Marvell and Lumentum market value at the close, 28 October vs 29 October 2026, US$ billions: Marvell about $220.7 billion to $191.5 billion, Lumentum about $82.0 billion to $82.5 billion. Market values are our arithmetic from closing prices and filing-date share counts. Sources: Nasdaq closes via Yahoo Finance; Marvell 10-Q; Lumentum 10-K.
The Arithmetic Behind the $29 Billion
Marvell’s 10-Q lists 876.9 million shares outstanding at 21 August 2026. By our arithmetic, that puts its value at about $220.7 billion at the 28 October close and about $191.5 billion at the 29 October close, a drop of about $29.2 billion. Bloomberg had put Marvell’s value at about $221 billion.
Lumentum’s 10-K lists 89.7 million shares at 14 August 2026, which by our arithmetic gives about $82.0 billion at the 28 October close and about $82.5 billion at the 29 October close. Bloomberg had put it at about $83 billion.
By our arithmetic, Lumentum’s value went from about 37% of Marvell’s to about 43% in one session. Lumentum’s close was also about 22% above its $752.54 close of 22 October.
What Marvell Would Be Buying
Our first piece on the talks set out Lumentum’s filings. Its fiscal 2026 revenue was $3,014.0 million, up 83.2%, and it guided $1.225 billion to $1.275 billion for the quarter to September 2026. Its annual report lists two unnamed end customers at 26.6% and 15.0% of fiscal 2026 revenue.
Marvell reported revenue of $2,739.3 million for its quarter to 1 August 2026, with data center revenue of $2,171.5 million, 79% of the total. On 23 October it disclosed, in an 8-K, a revolving credit agreement for borrowings of up to $3 billion.
As we read the session, the market priced the reported talks into the buyer, not the target: Marvell closed down 13.24% while Lumentum closed up 0.61%, after trading up 6% in the morning, 24/7 Wall St. reported.
By our arithmetic, Lumentum’s value rose from about 37% of Marvell’s to about 43% in one session, which matters for any deal paid in Marvell shares.
As we read the filings, Lumentum’s two largest end customers supplied 26.6% and 15.0% of its fiscal 2026 revenue, so a buyer would take on that concentration.
Bloomberg, 28 October 2026
“Marvell Technology Inc. is in advanced talks to buy data center optics maker Lumentum Holdings Inc., according to people familiar with the matter, a potential megadeal amid the race to scale up in the artificial intelligence sector”
Three Implications
FOR MARVELL SHAREHOLDERS The Motley Fool described the deal as reportedly all-stock and wrote that investors weigh financing and integration risks.
FOR LUMENTUM SHAREHOLDERS Lumentum closed at $919.53, about 22% above its 22 October close by our arithmetic, with no price or terms announced.
FOR THE OPTICS SUPPLY CHAIN Coherent closed at $237.22 on 29 October; Lumentum guided $1.225 billion to $1.275 billion of revenue for the quarter to September 2026.
The framework sets out to map the financing of AI: “How the money flows, where it cracks, what it buys, who can absorb it, and what happens when revenue can’t catch up.”
As we read it, the 29 October session is a question of “who can absorb it”: the market took about $29.2 billion off the buyer in a reported all-stock deal. The framework was published in May 2026 and does not discuss Marvell or Lumentum.
What Is Not Established
Neither company has announced a deal or confirmed talks in a filing or release we have seen. The price, structure and financing are not established; the all-stock description is the Motley Fool’s, citing reports. Market values are our arithmetic from filing-date share counts and may differ from current counts.
This Week In The AI Supercycle
Execution Fault Lines, Concentrated Demand, and Geopolitical Firewalls
This week’s issue: the AI build is not short of demand for its parts. It is short of cheap money, and its end revenue rests on a narrow base of large, often venture-funded buyers.
Marvell closed down 13.24% on 29 October after Bloomberg reported it is in advanced talks to buy Lumentum. By our arithmetic, that took about $29.2 billion off its market value, about 35% of Lumentum’s, while Lumentum closed up 0.61%.
A note on sourcing. The talks were reported by Bloomberg on 28 October 2026, citing people familiar with the matter. Closing prices and volumes are Nasdaq data via Yahoo Finance; intraday figures are from 24/7 Wall St. and the session description from The Motley Fool. Share counts come from Marvell’s 10-Q and Lumentum’s 10-K cover pages; market values and ratios are our arithmetic. We did not contact Marvell or Lumentum.
Gennaro Cuofano is a CRO and tech executive who has worked in AI since late 2015, starting with bringing NLP, natural-language generation, voice and chatbot products to the marketing industry. His background is in law and finance: he holds a Master's degree in Law and an International MBA with an emphasis on corporate finance (LUISS Business School and the University of San Diego, 2012), and worked as a financial analyst at a real-estate investment firm in San Diego and as an assistant controller. His work focuses on business model strategy, business engineering and, more broadly, structural analysis: how companies make money, read from their own filings. He created FourWeekMBA and leads research there and at The Business Engineer, his newsletter on AI and business strategy, with over 95,000 subscribers and more than 1,000 published analyses. His writing has also appeared on Entrepreneur (for example, How to Digitize a Family Business in Europe) and HackerNoon. Find him on LinkedIn and Substack. See how we source.
