Optics Stocks Tumble as Profit Taking Cuts Into Big Yearly Gains: Applied Optoelectronics Drops 9%, Coherent Falls 5%, Lumentum Slides 4%

Optical component stocks are bleeding out after one of the most spectacular sector runs in recent memory, and the selling pressure tells a more complicated story than simple profit taking.

Published October 8, 2026, 12:00pm ET · 3 min read

Market Movers desk. Editor: David Moadel.

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Optical component makers are being sold as a group after a year of extraordinary gains, and the pressure is landing hardest on the names that ran furthest. Shares of Applied Optoelectronics (NASDAQ:AAOI) are down 9% to $111.76 in morning trading, the steepest drop among the group’s leaders. Applied Optoelectronics stock is up 221% so far this year, a gain that leaves plenty of room for profit taking.

Meanwhile, Coherent (NYSE:COHR | COHR Price Prediction) stock is down 5% to $316.40, a smaller slide that still places the larger laser maker squarely in the selloff. Lumentum (NASDAQ:LITE) stock is falling 4% to $1,068.50, the mildest decline of the trio. Lumentum stock is up 190% so far this year, which shows how much ground the group covered before this pullback.

For a sector-wide read, the Roundhill Photonics & Optics ETF (CBOE:LYTE) is down 6% to $24.89, a steeper drop than either Coherent stock or Lumentum stock. As a broad-market check, the SPDR S&P 500 ETF Trust (NYSEARCA:SPY) is down 0.4% to $774.35, so large caps are nearly flat while the photonics trade unwinds.

Profit Taking Spreads Across Optical Suppliers

Applied Optoelectronics, Coherent and Lumentum shares are falling together, a pattern pointing to profit taking across optical suppliers after an exceptional run. The photonics fund is losing more ground than either Coherent stock or Lumentum stock, marking this as a move across the whole group. The steepest declines are landing in the stocks that climbed fastest during the artificial intelligence data center buildout.

Lumentum and Coherent rank among the fund’s top holdings, with Applied Optoelectronics a far smaller position. As a result, the two larger names carry heavy influence over its moves.

Applied Optoelectronics designs and builds optical transceivers and components. It does this in its own plants, tying the company’s earnings to production yields, volume and pricing on a narrow product set. That sensitivity is on full display in this selloff.

Weighing the Bull and Bear Cases

Applied Optoelectronics bulls point to optical interconnect demand from artificial intelligence data centers, the same force that lifted shares in the first place. Nothing the company has disclosed alters that demand picture, so supporters can frame the drop as a positioning reset.

A stock carrying gains of this size has already priced in a great deal of that demand, which is central to the bear case on Applied Optoelectronics. The company is exposed whenever positioning shifts, and its narrow product set gives investors fewer offsets when sentiment cools.

Coherent and Lumentum offer a steadier version of the same trade, with broader end markets that soften the blow from any one demand signal. Lumentum stock still carries an enormous gain this year, so the larger names remain vulnerable when the group unwinds.

What to Watch Now

Traders can watch this relative slide. Pay special attention to whether the LYTE photonics fund keeps sliding faster than Coherent stock and Lumentum stock, since that gap separates a group-wide unwind from a reset in a few crowded names. A rebound in the SPDR S&P 500 ETF Trust alone may do little for a corner of the market that dropped while large caps barely moved.

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David Moadel

David Moadel is financial writer specializing in stocks, ETFs, options, precious metals, and Bitcoin. David has written well over 1,000 articles for leading online publications, helping investors understand markets, income strategies, and risk.His work has appeared in The Motley Fool, InvestorPlace, U.S. News & World Report, TipRanks, ValueWalk, Benzinga, Market Realist, TalkMarkets, Finmasters, 24/7 Wall St., and others.With a master’s degree in education, David has taught at the elementary, high school, and college levels. That teaching background shapes his writing style: clear, educational, and practical. David has also built a loyal social-media audience by providing trustworthy financial content on YouTube, X/Twitter, and StockTwits.

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