Why Lumentum Trades 30% Below Marvell's $1,132 Offer: The Fixed-Ratio Math Behind a $115B Deal

Lumentum (LITE) was trading near $788.51 in Monday morning trading, about 30% below the $1,132 per share that Marvell Technology (MRVL) put on its $115 billion all-stock offer. The gap is not a sign that investors expect the deal to fail. Lumentum holders are to receive a fixed 4.5 Marvell shares for each of their shares, so the offer is worth whatever 4.5 Marvell shares are worth, and Marvell has fallen about 24% since the $1,132 figure was struck.

The fixed-ratio math

The $1,132 headline price is 4.5 times Marvell's $251.65 close on Oct. 28, the last session before news of the talks, and it represents a 23.9% premium to Lumentum's $913.95 close that day. The release describes no collar or other adjustment to the ratio, so a lower Marvell price passes straight through to Lumentum holders.

By our calculation, the offer at Monday's Marvell price is worth about 6% less than Lumentum's unaffected Oct. 28 close. Lumentum holders are being offered, in effect, less than the stock was worth before the deal. That, more than the merger itself, explains why the shares are down.

Why Lumentum is down even with a buyer

• It is tied to Marvell. With a fixed ratio, Lumentum behaves like a claim on 4.5 Marvell shares. Marvell fell about 10% in the prior session and about 3% on Monday morning, and Lumentum fell about 9% and about 6%.
• Doubts about the currency. Marvell is issuing stock equal to roughly a third of the combined company, since Lumentum holders would own about 33%. Investors are weighing that dilution and the size of the deal against a market already wary of AI hardware spending.
• A long wait. Closing is expected in the first half of calendar 2028, so holders carry market, sector and Marvell-specific risk for well over a year.
• Approvals. Both companies' stockholders and regulators must approve. The release does not say which regulators or what vote thresholds apply.
• A like-for-like gap. The $115 billion is an implied enterprise value, which includes debt and other claims net of cash. A market capitalization of about $68 billion, based on market data, measures only the equity, and the release gives no equity value, so the two figures are not directly comparable. By our calculation, a 30% lower price alone would take $115 billion to about $80 billion; the remainder of the gap is consistent with the enterprise-versus-equity difference but cannot be sized from the release.

How big is the merger spread?

Merger arbitrage is the practice of buying the target and selling the acquirer short to capture the gap between them. At Monday's morning prices, 4.5 Marvell shares are worth about $857, or about 8.7% more than Lumentum's price, by our calculation. If the deal closes between January and June 2028, that is roughly 5% to 7% a year before costs, compared with a Federal Reserve target range of 3.75% to 4%.

That is a thin cushion over short-term rates for a deal that needs two shareholder votes and a global antitrust review. It suggests the market is pricing a fairly high chance of completion, and that most of Lumentum's decline is the mark-to-market on Marvell shares rather than a wider risk discount. Those annualized figures are by our calculation and ignore borrowing costs on the short Marvell position and dividends.

What the offer would be worth at different Marvell prices

The table is illustrative arithmetic, not a forecast. By our calculation, Lumentum would need Marvell at about $203 to return to its $913.95 unaffected close with no spread, or about $221 if it still traded at an 8% discount.

What to watch

• The Form S-4. Marvell plans to file a joint proxy statement and prospectus, which should disclose the background of the talks, vote requirements, termination fees and other terms the announcement left out.
• Marvell's share price. Every $10 move in Marvell changes the value of the offer by $45 per Lumentum share, by our calculation.
• The spread. A widening beyond 8% to 9% would signal growing doubt about approvals or timing; a narrowing would signal confidence.
• Antitrust signals. Early comments from regulators on a $115 billion combination in optical and electrical connectivity would move the odds.
• Fundamentals. Lumentum guided fiscal second-quarter revenue to $1.575 billion to $1.625 billion, and Marvell narrowed its fiscal third-quarter range to plus or minus 2%. Details are in our news article on the deal.
• Market backdrop. Scrutiny of AI spending is weighing on the group. See our Research Desk analysis and the Week Ahead article.

Sources: Marvell Technology announcement of the combination with Lumentum and its Form 8-K. Share prices are from market data in morning trading on Nov. 2 and will change. Items labeled by our calculation are our own arithmetic. This article is informational only and is not investment advice.