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FORM Insider Trading and Fund Holdings (FORMFACTOR INC) · https://wallstpal.com/stock/form/ · saved 2026-10-28

About this page

Insider trades reported on SEC Form 4: when the people who run a company buy or sell its shares with their own money.

How to read it

Form 4
The form a company insider (officer, director or owner of more than 10%) must file with the SEC within two business days of buying or selling the company's shares.
Buy (P) and Sell (S)
Open-market purchases and sales. Gifts, option exercises and automatic tax withholding are left out because they say little about what the insider thinks.
Value
Shares times price, as reported on the filing.
10b5-1
A trade made under a plan set up in advance. Planned sales are common and usually say less than an unplanned purchase.
Late filing
A Form 4 filed more than two business days after the trade.
Vs. S&P 500
How the stock did after the trade minus how the overall market did in the same weeks.

A real example

In January 2016, when bank stocks were falling, JPMorgan Chase CEO Jamie Dimon bought 500,000 JPMorgan shares with his own money, worth about $26 million. His Form 4 made the purchase public within days, and investors read it as a strong sign of confidence.

Explain it like I'm 13

If the coach of a team bets his own allowance that his team will win, that tells you something. A Form 4 is the note a company boss must hand in whenever he buys or sells his own company's shares, so everyone can see it.

Data from public SEC filings and congressional reports. Information, not investment advice. Check every number against the filing linked on the page.

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StockCIK 1039399

FORMFACTOR INC (FORM): Insider Trades and Fund Holdings

In the past 12 months, FORMFACTOR INC insiders reported no open-market purchases and 4 sales worth $5.52M; 3 of the sales were reported as made under a 10b5-1 trading plan.

0Insider buys, 12 months
$0Bought by insiders, 12 months
$5.52MSold by insiders, 12 months
2Tracked funds holding

Timeline: news and trades

Company filings (8-K), insider trades, notices of planned sales (Form 144) and fund moves in the past year, newest first.

  1. Oct 14, 2026Insider saleCEO Mike Slessor sold $1.4 million under a 10b5-1 plan
  2. Oct 14, 2026Planned saleMIKE SLESSOR (officer, director) filed notice to sell about $1.4 million around Oct 14, 2026
  3. Sep 16, 2026Insider saleCEO Mike Slessor sold $1.8 million under a 10b5-1 plan
  4. Sep 16, 2026Planned saleMIKE SLESSOR (officer, director) filed notice to sell about $1.8 million around Sep 16, 2026
  5. Sep 3, 2026Insider saleDirector Kelley Steven-Waiss sold $201,810
  6. Sep 3, 2026Planned saleKELLEY LYNNE STEVEN-WAISS (director) filed notice to sell about $201,810 around Sep 3, 2026
  7. Aug 14, 2026Insider saleCEO Mike Slessor sold $2.1 million under a 10b5-1 plan
  8. Jun 30, 2026FundBridgewater Associates added 224% in Q2 2026 (13F filed Aug 14, 2026)
  9. Jun 30, 2026FundRenaissance Technologies opened a position in Q2 2026 (13F filed Aug 13, 2026)

Recent insider trades

Open-market purchases (code P) and sales (code S) from Form 4. Grants, option exercises and gifts are not shown. Latest filing: Oct 14, 2026.

Recent FORM insider trades
FiledTradedInsiderRoleTypeSharesPrice ($)ValueHoldingFiling
Oct 14Oct 14Mike SlessorCEOCEO▼ SELL10b5-111,098125.20$1.39M−2.4%Form 4 ↗
Sep 17Sep 16Mike SlessorCEOCEO▼ SELL10b5-117,510104.73$1.83M−3.6%Form 4 ↗
Sep 4Sep 3Kelley Steven-WaissDirectorDirector▼ SELL2,10096.10$202K−7.9%Form 4 ↗
Aug 17Aug 14Mike SlessorCEOCEO▼ SELL10b5-116,002130.95$2.10M−3.2%Form 4 ↗
Source: SEC Form 4 filings, retrieved Oct 28, 2026. How we read filings

Insiders who traded in the past year

InsiderRoleBuysBoughtSellsSoldLatest
Mike SlessorCEO0$03$5.32MOct 14, 2026
Kelley Steven-WaissDirector0$01$202KSep 4, 2026

Buybacks and executive pay

FORMFACTOR INC spent $26.2 million buying back its own shares in 2025.

From the company's XBRL data filed with the SEC. "Actually paid" is the SEC's pay-versus-performance measure, which counts changes in the value of stock awards. "Value of $100 invested" is the company's cumulative shareholder return as reported, usually measured from five years earlier. See all buybacks and CEO pay across companies.

Tracked funds that report FORM

From each fund's latest 13F. Holdings are as of quarter end and are filed up to 45 days later.

FundQuarterSharesValue% of portfolioChange
Renaissance TechnologiesQ2 2026295,568$47.3M0.07%▲ New
Bridgewater AssociatesQ2 2026162,592$26.0M0.11%▲ +223.8%
Source: SEC Form 13F-HR filings, retrieved Oct 28, 2026. How we read filings

Reading these numbers

Insiders sell for many reasons: taxes, diversification, a house. Purchases with their own money are rarer and are usually read as more informative. A Form 4 is due within two business days of the trade. How to read a Form 4 →