A maker of the vacuum gauges, lasers, and specialty chemicals that help produce computer chips, circuit boards, and other high-tech goods, MKS supplies the tools factories rely on to build modern electronics. It was founded in 1961 in a Massachusetts garage after Sidney Siegel built a device to measure low-pressure gases, and its name comes from the Meter-Kilogram-Second system of measurement. That first gadget, the Baratron manometer, became essential to making microprocessors — a fitting start for a company still helping power the digital world.
Select a row to see that insider’s individual transactions. † Sum of the holdings confirmed in the 12 months before this insider's last filing. A Form 4 reports a holding per line — held directly, or through a named trust, partnership or foundation, and in each share class separately — never a person’s total. Lines not restated in that time are left out and shown apart: an active filer restates what they still hold, so a line they did not restate is more often an entity since renamed, whose shares a successor line reports too. An amber marker means some were left out.
Net open-market activity over the last 6 months: -72.6K shares. Grants, option exercises and tax withholding are excluded — they are compensation mechanics, not decisions to buy or sell.