FORM · FormFactor, Inc.

The thesis

FormFactor's probe cards for high-bandwidth memory (HBM) and AI processors tie its revenue to a record memory spending cycle, but the shares now trade only a few dollars above the level that breaks the case. The third-quarter report, expected around 28 October 2026, settles it: revenue has to clear the $260 million floor of the company's own guidance, and the fourth-quarter outlook has to keep growing.

Probe cards are the test hardware that checks memory and processor chips while they are still on the wafer. The shares closed at $141.30 on 6 October 2026, their first session in the S&P MidCap 400, down from $147.99 on 5 October 2026 (adjusted daily closes). That close sits 11.6% below the 52-week high of $159.93 and just above $136.25, the 29 September 2026 close before the Deutsche Bank initiation. Zacks put the year-to-date gain at 164.6% on 6 October 2026.

The narrative is maturing: the 30 September 2026 Deutsche Bank initiation and the 1 October 2026 index announcement brought the story to a wide audience, and the first session after index buying ended brought a decline. The business evidence still points up. With the price this close to the invalidation level and momentum still stretched, the shares look more likely to lag the S&P 500 than lead it over the next three months. That view is wrong if the shares hold above $136 into the report and third-quarter revenue lands above the $270 million guidance midpoint.

Bullish and bearish views on FormFactor, Inc.

The bull case on FormFactor, Inc. (FORM), in brief: The guided quarter is already closed. The bear case: Momentum is still stretched.

Bull case

• The guided quarter is already closed. FormFactor's third quarter ended 26 September 2026. On 29 July 2026 the company guided revenue to $270 million ± $10 million and non-GAAP earnings to $0.86 ± $0.09 per diluted share, after second-quarter revenue of $258.2 million, up 14.2% sequentially and 31.9% year over year (second-quarter release, Form 8-K).
• Second quarter beat the top of guidance. The 29 July 2026 release said revenue, gross margin and earnings per share all exceeded the high end of the GAAP and non-GAAP outlook ranges, and it guided third-quarter non-GAAP gross margin to 54.0% ± 1.5 percentage points.
• Memory customers are posting record results. Micron reported fiscal fourth-quarter revenue of $54.23 billion and a non-GAAP gross margin of 87.0% on 30 September 2026, and guided the next quarter to $61.5 billion ± $1.5 billion (Micron release).
• A GPU probe-card path has a public estimate. Deutsche Bank's 30 September 2026 initiation, with a Buy rating and a $200 target, names FormFactor the second probe-card source for Nvidia GPUs made at TSMC, with first sales in the second half of 2026 (Investing.com and Benzinga reports of the note).
• Skeptics are raising targets. Freedom Capital Markets kept a Hold rating on 5 October 2026 but raised its target from $64 to $140 (GuruFocus).

Bear case

• Momentum is still stretched. The 14-day relative strength index (RSI), a momentum gauge where readings above 70 mark a stretched advance, stood at 81.3 at the 6 October 2026 close after 92.2 on 5 October 2026.
• Index demand has run its course. FormFactor moved from the S&P SmallCap 600 to the MidCap 400 before the open on 6 October 2026 (S&P Dow Jones Indices, 1 October 2026). The shares closed that day at $141.30, below every close of the prior four sessions.
• Earnings estimates are slipping. Zacks reported on 6 October 2026 that the consensus 2026 earnings estimate fell a couple of cents over 30 days to $3.03 per share, while the shares kept rising.
• Most targets sit near or below the price. Freedom Capital Markets' $140 target (5 October 2026) and TD Cowen's $100 target with a Hold rating (30 July 2026) are both under the 6 October 2026 close. Deutsche Bank's $200 is the high end.
• HBM share is under pressure. Deutsche Bank expects FormFactor to cede about 40% of HBM probe-card share to Technoprobe (Investing.com, 30 September 2026).
• Valuation is rich and insiders are selling. GuruFocus put the trailing price-to-earnings ratio at 101.4 times on 5 October 2026 and counted $4.69 million of insider sales over three months. Chief executive Mike Slessor sold 15,602 shares at $128.72 to $133.33 on 14 August 2026 under a Rule 10b5-1 plan (SEC Form 4).

Price setup

The shares closed at $136.25 on 29 September 2026, jumped after the Deutsche Bank initiation, and held between $147.99 and $149.31 across the four sessions to 5 October 2026. The 6 October 2026 close of $141.30 broke below that range. The 52-week high is $159.93.

Two levels frame the next three weeks. The $147.99 to $149.31 closing range is the area the shares fell out of on index day. The $136.25 close of 29 September 2026 marks the start of the initiation rally; a daily close below $136 would give back the whole move. The shares rose 18.3% over three months on adjusted daily closes, and the 14-day RSI of 81.3 shows the advance has not yet cooled.

Catalysts, next 30 days

• ~28 October 2026 (est.) — FormFactor third-quarter 2026 results. The company has not yet confirmed the date; last year's third-quarter report came on 29 October 2025. Revenue against the $260 million to $280 million range and the fourth-quarter guide decide the case.
• ~29 October 2026 (est.) — SK hynix and Samsung full third-quarter results. HBM capacity plans and HBM4 qualification comments from the two largest HBM makers test the demand behind memory probe cards.

Elapsed catalysts

• 8 October 2026 — Samsung Electronics preliminary third-quarter results. Seoul Economic Daily reported on 4 October 2026 that analysts expect operating profit above 110 trillion won. A miss would be the first crack in the memory spending story ahead of FormFactor's own report. (passed 8d ago)

What would change the view

The case breaks on the report. Third-quarter revenue below $260 million, the floor of the 29 July 2026 guidance, would show that record memory spending is not reaching FormFactor's income statement. A fourth-quarter revenue guide flat or below the third-quarter result would end the growth argument. Silence or a stated delay on first Nvidia GPU probe-card shipments at TSMC would remove the part of the case that Deutsche Bank's $200 target rests on.

On price, a daily close below $136 would erase the rally that began with the 30 September 2026 initiation. In the other direction, revenue above the $280 million top of guidance with a higher fourth-quarter outlook, and closes back above the $149.31 high of early October, would show buyers absorbing the end of index demand and would lift the case.

What it trades with

FormFactor trades with memory capital spending. Results and guidance from Micron, SK hynix and Samsung move the shares, because DRAM and HBM probe cards are a large part of its revenue. It also trades with the semiconductor test and equipment group, including Cohu, Axcelis, Veeco and TSMC as a key foundry customer. Since 6 October 2026 the shares sit in the S&P MidCap 400, so mid-cap index flows replace small-cap ones. The Nvidia GPU probe-card opportunity adds sensitivity to AI accelerator demand at TSMC.