FormFactor's Record Quarter Meets a Capacity Constraint

FormFactor delivered its fourth consecutive quarterly revenue record, but the stock fell 12% after management warned that productivity gains at its existing factories are tapering as those sites approach capacity. The tension is straightforward: demand is strong, yet the bridge to new capacity could flatten near-term growth and trim margins before the next factory is fully productive.

Revenue reached $280.5 million in the fiscal third quarter ended September 26, up 8.6% from the second quarter and 38.4% from a year earlier. GAAP net income was $73.8 million, or $0.93 per diluted share. On the company's adjusted basis, net income was $82.3 million, or $1.04 per diluted share. The distinction matters because the adjusted figures exclude stock compensation, amortization and restructuring costs.

The fourth-quarter forecast explains the market's hesitation. FormFactor guided to $285 million of revenue, plus or minus $10 million, which puts the midpoint only 1.6% above the third quarter. It expects GAAP gross margin of 52.3%, plus or minus 1.5 percentage points, and adjusted gross margin of 54.0%, also plus or minus 1.5 points. Both midpoints are below the third quarter's 54.7% GAAP and 56.5% adjusted margins.

The constraint is manufacturing, not a stated demand shortfall. CEO Mike Slessor said gains from the existing footprint are moderating as the company approaches its capacity limits. FormFactor has opened a nearly 300,000-square-foot facility in Farmers Branch, Texas, for advanced probe cards. Management said the site shipped its first production unit and is intended to support about $400 million of annual probe-card revenue capacity by the end of 2027. That timetable creates execution risk: startup costs and a gradual ramp arrive before the full revenue benefit.

The underlying demand indicators remain strong. Foundry and Logic revenue rose 10% sequentially to $134.0 million, while Systems revenue increased more than 20% to $59.5 million as demand for co-packaged optics grew. Operating cash flow reached $104.3 million and free cash flow was $64.8 million, giving the company room to fund expansion. Teradyne also agreed to invest about $300 million for a minority stake, subject to closing conditions, alongside a collaboration on next-generation semiconductor test systems.

Customer concentration is the counterweight to that momentum. SK hynix accounted for 20.7% of third-quarter revenue and Taiwan Semiconductor Manufacturing accounted for 12.8%. Together they represented one-third of sales, so changes in either customer's spending can move results quickly.

The next external check comes November 9, when Onto Innovation is scheduled to report results. Strong advanced-packaging demand across the group would support FormFactor's claim that its pause is capacity-led. The more important company-specific test is whether Farmers Branch scales without extending the margin dip. Record demand has created a valuable bottleneck, but investors still need evidence that the new factory can convert it into profitable growth.