A sharp pullback in optical networking stocks has erased billions in market value as investors reassess valuations following a prolonged rally driven by AI datacenter demand. Coherent (COHR), Lumentum (LITE), Corning (GLW) and Ciena (CIEN) all posted weekly declines of 10% to 18% as of August 21, with the group now trading 20% to 45% below their 52-week peaks despite strong year-to-date gains.
The sector’s recent surge—with gains ranging from 54% to 135% year-to-date—was largely attributed to demand for fiber-optic components tied to artificial intelligence infrastructure. However, the momentum stalled last week as hedge funds reduced exposure to technology equities at the fastest pace in two months, according to Goldman Sachs data. The de-grossing in tech marked the largest percentage reduction in over two years, accelerating declines across the optical space.
Valuation metrics remain a point of contention. Ciena, trading at $395.79, is valued at 127.8 times trailing earnings and 58.8 times forward estimates, with a fair value gap of 35.9% below current levels. Lumentum, despite its 83.2% revenue growth, carries a forward price-to-earnings ratio of 35.6x and is assessed as 18.5% overvalued. Corning, while trading at a more moderate 45.2x forward earnings, has fallen 45% from its peak and maintains a 20-year dividend streak. Coherent, down 34% from its 52-week high, reported 22.5% revenue growth but saw 18 analyst estimate revisions upward.
Technical indicators have turned bearish across the board. Daily and weekly signals for all four stocks are uniformly flagged as "Strong Sell," with Relative Strength Index readings between 44 and 53—just above oversold territory. StochRSI signals suggest some names may be approaching oversold conditions, though not yet at levels typically associated with capitulation.
Additional headwinds include dilution concerns and competitive pressures. Applied Optoelectronics (AAOI) launched a $600 million at-the-market stock offering in August, equivalent to 5.7% of its equity value, its third such program in 2026. Ciena’s correction from a June peak was also influenced by investor recognition of competition from Nokia and Cisco in the optical networking market, which had previously been underestimated.
Analysts remain cautiously optimistic on the sector’s long-term prospects. Rosenblatt Securities projects Ciena to report $1.70 billion in revenue for its fiscal fourth quarter ending September 3, above the $1.63 billion consensus, with adjusted earnings per share of $1.90 versus $1.72 expected. The firm maintains a $720 price target for Ciena, implying 82% upside from its August 21 close. Across the group, analyst targets suggest potential gains of 34% to 39% from current levels, though most models still indicate overvaluation relative to fair value estimates.
The sector faces a critical test with Ciena’s earnings release on September 3, which could provide clarity on demand trends and margin sustainability amid the broader market volatility.
