Is Onto Innovation (ONTO) Undervalued Amid AI Packaging Momentum and Analyst Upgrades?

The semiconductor equipment sector has long been a barometer for technological innovation, and Onto Innovation (ONTO) has emerged as a focal point of debate amid its recent rally. With AI-driven advanced packaging and the Semilab acquisition fueling optimism, investors are grappling with a critical question: Is ONTO's current valuation a realistic reflection of its growth trajectory, or is the market overbidding future demand?

Financial Performance and Analyst Sentiment: A Mixed Picture

Onto Innovation's Q3 2025 results underscored its resilience in a volatile market. Revenue of $218.2 million exceeded guidance midpoints, driven by robust demand in advanced packaging and memory technologies. Adjusted earnings per share (EPS) hit $0.92, aligning with the high end of expectations, while Q4 revenue guidance of $250–265 million signals 15–21% sequential growth. Analysts have responded with upgraded price targets, including a $180 target from Oppenheimer, reflecting confidence in the company's AI packaging capabilities and offshore manufacturing progress.

However, valuation metrics tell a nuanced story. The stock trades at a forward P/E of 32.33, in line with the industry average, but some sources report a P/E of 44.4x, which exceeds the sector's 36.8x average according to industry analysis. This discrepancy highlights divergent views on ONTO's growth potential. Meanwhile, a PEG ratio of 1.08 suggests the stock is fairly valued relative to its projected earnings growth, though it lacks a clear discount to intrinsic value.

AI Packaging Momentum: A Double-Edged Sword

The AI packaging market is projected to grow at a compound annual rate of 13.51%, with Onto Innovation positioned to benefit from its 3Di and Dragonfly systems, which cater to high-bandwidth memory and AI computing needs. The company's Q3 specialty devices and advanced packaging revenue reached $113 million according to earnings data, and full-year expectations remain at $300 million as reported in Q3 results.

Yet, ONTO's market share in the semiconductor equipment industry remains modest at 1.55% as of Q1 2025. While its alignment with AI trends is compelling, the sector's concentration of giants like ASML and Lam Research means Onto must differentiate through niche innovations. The Semilab acquisition, valued at $495 million, is a strategic move to bolster materials analysis capabilities, but its immediate financial impact is limited-adding $8–10 million in revenue within six weeks and $0.02 to EPS. Analysts argue this positions ONTO for long-term margin expansion.

The key tension lies in reconciling ONTO's current valuation with its growth narrative. At a market cap of $5.91 billion, the company is projected to reach $1.4 billion in revenue by 2028 according to market analysis, implying an 11% annual growth rate. This trajectory would require sustained demand for AI packaging, a sector still in its infancy. While North America dominates the AI packaging market with 38.89% share according to industry reports, the Asia-Pacific region's rapid industrialization could introduce new competitors, diluting ONTO's edge.

The PEG ratio of 1.08 suggests the stock is neither undervalued nor overvalued relative to its growth, but the wide range of P/E estimates (32.33x to 44.4x) reflects uncertainty. If ONTO meets its 2028 revenue target of $1.4 billion, a forward P/E of 32.33 would imply a stock price of approximately $175, aligning with analyst price targets. However, this assumes no material headwinds in AI adoption or margin pressures from tariffs as highlighted in Q3 earnings or integration costs.

Risks and Rewards

Investors must weigh several risks. First, the AI packaging market's growth projections are speculative, with 2032 estimates relying on assumptions about generative AI's adoption in data centers. Second, Onto's reliance on memory and AI sectors exposes it to cyclical downturns, as evidenced by its 13.5% year-over-year revenue decline in Q3. Third, the Semilab acquisition, while strategic, could strain cash flow or underperform if integration proves challenging according to financial analysts.

Conversely, the company's disciplined cost controls, strong Q4 guidance, and alignment with NVIDIA's advanced packaging priorities offer a compelling case for optimism. Analysts' revised price targets and the projected $311.2 million in 2028 earnings suggest the market is pricing in a recovery in memory demand and sustained AI-driven growth.

Conclusion: A Tug-of-War Between Caution and Confidence

Onto Innovation's valuation sits at a crossroads. While its financials and strategic moves-particularly the Semilab acquisition-justify a premium, the stock's current price lacks a clear margin of safety. For investors with a medium-term horizon, ONTO could be a speculative play if AI packaging adoption accelerates as expected. However, those seeking undervaluation may find the P/E and PEG metrics insufficiently compelling. The key takeaway is that ONTO's success hinges on its ability to execute its AI packaging narrative without overreliance on macroeconomic tailwinds.

In the end, the stock's trajectory will likely mirror the semiconductor industry's broader fortunes. For now, the market's optimism appears cautiously justified-but not without risks.