Pull factor: who makes the magnet inside a humanoid?

The magnets inside a humanoid’s joints matter more than anything you see when it walks across a stage. They help the small motors in its arms and legs produce enough force to move the robot. As the Foundation for American Innovation (FAI) points out, robot makers do not tell us what grade of magnets they use.

FAI puts the magnet in a humanoid at 2 to 4.5 kilograms, against about 1.4 kilograms in an electric car. The lower figure fits Western robots, which use heavier gearing; the higher fits Chinese designs, which use less. Rare earths are metals used to make these powerful magnets. A 2023 Aspen Institute report estimates that China makes 92 percent of the world’s rare-earth magnets. By weight, a humanoid carries about one and a half to three times as much magnet as a car. FAI adds that car magnets need 2.8 times as much of the scarce heavy rare earths per kilogram, so one car uses about as much of them as 1.2 humanoids.

Two of those metals, dysprosium and terbium, help magnets keep working when they get hot, and almost none is produced outside China’s sphere of influence. Since April 2025, anyone exporting seven of the heavier rare earths, or magnets containing them, has needed Chinese government permission. That licence stays in force. A wider set of rules from October 2025 is on hold, and on Monday Beijing extended the pause to 10 January 2027. One paused rule would extend the controls to certain products made outside China that contain Chinese rare earths. Depending on how it is applied, that could include a German or American motor with Chinese magnets inside. I doubt Beijing is trying to stop robot makers: electric cars already use as much of these heavy rare earths as 26 million humanoids would in a year, FAI estimates. Even so, I’d ask who makes the magnet inside a humanoid’s joints, because on Aspen’s estimate it is mostly one country.

Washington has also acted on robot imports, and it hasn’t said which parts it means. On 28 October, the White House issued a proclamation under Section 232, a US law that lets the president restrict imports on national-security grounds. The text lists humanoid and four-legged robots among advanced robots that provide combat support to the US military. There are no new import taxes yet. Law firm Troutman Pepper Locke says it gives no list of product codes showing which parts are covered, and advises importers to assume parts may be included. So whether a joint motor, or the magnet inside it, counts is an open question.

Musk raised the magnet problem on Tesla's April 2025 earnings call. He said China's export restrictions had affected Optimus because its arm actuators use permanent magnets. In October 2026, he put a number on the delay: two to three months. The Chinese export rule Musk blamed for that delay is still in force.

Schaeffler is a German company that makes components for cars and factory machinery. It is cutting 3,460 jobs across Europe while building a business supplying components for humanoid robots.

On CNBC, CEO Klaus Rosenfeld said the company was rearranging capacity to “free up ... capacity for the new things that are coming,” and named robotics and defence as those new areas. Schaeffler blames the cuts on weak demand for combustion-engine parts and high labour costs. Its humanoid business now carries a headline figure of €400M, which the CEO called “orders on hand” in Schaeffler’s 13 October results release, meaning orders booked for later delivery. The release said new customers in Greater China contributed to the figure. It did not name them, or give a unit count or delivery period.

In the August earnings call, Rosenfeld said the order book aka "orders on hand" counts only signed orders for series production, meaning volume manufacturing, with customer estimates cut substantially to stay conservative. Those customers were due to start production within months. Schaeffler has not said how many robots’ worth of parts the orders cover, or whether the customers added since are included in that schedule. Rosenfeld also said the business needs time to scale before it shows in Schaeffler’s accounts.

The humanoid robot footprint at Schaeffler is spread across a few settings, not a single fleet. At the newly opened Taicang factory in China, Schaeffler says humanoids assemble robot components; its release does not name their maker. At Cheraw, South Carolina, Agility Robotics’ Digit moves baskets of bearing parts from a stamping press to a conveyor feeding a washer. In Germany, Hexagon’s AEON is still in Schaeffler’s Humanoid Gym, where it is being trained and tested before wider factory use. A separate deal announced by UK-based Humanoid schedules German-site deployments to begin in December. Hexagon and Schaeffler’s larger AEON rollout remains a 2032 target.

Schaeffler says most cuts should be implemented by 2028 and part of the reduction is to be offset by new positions in growth areas like humanoid robotics and defence. It has not said how many jobs these new businesses will create, where those jobs will be located, or whether they will appear near the sites losing positions. The cuts have a number and a deadline. The promised new jobs have neither.

This week, the Signal looks at the magnets inside a humanoid’s joints, which makers do not specify, and at what China’s two-month extension does and doesn’t change.

Below the Fold follows Schaeffler, which is cutting 3,460 jobs while reporting €400M of humanoid orders, and has given no number for the jobs it says new businesses will add.

Cars come up in both stories only in passing: electric cars already use as much of the scarce heavy rare earths as 26 million humanoids would, and Schaeffler, a car-parts maker, blames its cuts on weak demand for combustion-engine parts.