Formfactor FORM Insider Ownership

Updated Oct 10, 2026

Over the trailing 12 months, FORM insiders sold $21.3 million worth of shares (221.64K shares) in open-market trades, with no open-market purchases.

• Formfactor's open-market sales in the past 12 months came from 8 insiders; no insider bought.
• Mike Slessor (CEO) sold the most Formfactor stock on the open market over the past 12 months, $14.79 million (158.53K shares), most recently on September 16, 2026.
• In transactions other than open-market trades, Formfactor insiders received 1.35K shares in stock awards, acquired 211.82K shares through option exercises and conversions, gave up 115.67K shares to cover taxes or exercise prices and gave away 5.74K shares as gifts over the past 12 months.
• Business Quant data shows Formfactor insiders holding 639.67K shares in total in their latest Form 4 filings, up 5.03% from 609K shares at the end of Q2 2026 and down 16.96% from 770.3K shares at the end of Q3 2025.
• Formfactor insiders report no indirect holdings: all 639.67K shares are held directly.
• FORM's insider total is spread across 10 insiders who have filed a Form 4 in the past two years.
• Formfactor's three biggest insider holders are Mike Slessor (CEO, 466.69K shares), Shai Shahar (CFO, SVP Global Finance, 55.97K shares) and Thomas St. Dennis (Director, 28.33K shares), based on their latest Form 4 filings.
• Mike Slessor holds 72.96% of the combined insider position in Formfactor.
• Institutions held 92.00% of Formfactor's outstanding shares in their Q2 2026 13F filings, insiders about 0.82% based on their latest Form 4 filings, and other investors, including the public, the remaining 7.18%.
• In the last 12 months, 55 Form 4 filings with transactions in FORM stock came from 9 insiders.
• The insider data for FORM reflects Form 4 filings through September 17, 2026.