Samsung and SK Hynix have spent roughly two years quietly testing Chinese chip tools inside their own factories in China, according to three sources who spoke to Reuters. Samsung’s official response was to deny it. SK Hynix declined to comment. That gap, between what the sources describe happening on the factory floor and what the companies will say in public, is most of the story right there.

The equipment in question comes from Shanghai-based Advanced Micro-Fabrication Equipment, AMEC for short, and the trials are reportedly happening at Samsung’s NAND plant in Xi’an and at SK Hynix’s NAND site in Dalian and DRAM fab in Wuxi. Both plants currently lean on etching gear from Applied Materials and Lam Research, the American tool giants that have dominated this layer of chipmaking for decades. Qualifying a new tool isn’t something either company does casually, it means running it in real production long enough to prove it hits yield and reliability targets, and Reuters reports the trials started about two years ago, right when it was getting hard to guess whether Washington would keep letting US toolmakers ship into China at all.

The regulatory backdrop explains the timing. Washington designated Samsung’s and SK Hynix’s Chinese fabs as validated end users in 2023, which let them import certain controlled US equipment without a case by case license. That status got revoked in 2025, and both companies now operate under an annual license renewed for 2026. Equipment access is fine again for now. What worries them is the layer underneath it: servicing, repairs, and spare parts for the American and European machines already bolted to their factory floors. A license to buy a new tool today doesn’t guarantee you can get it fixed five years from now if the rules tighten again.

I’ve written before about China building its own domestic lithography tools to route around the ASML chokepoint, and about how export controls have a way of reshaping supply chains in directions nobody in Washington quite planned for. This is the same pattern showing up on the customer side instead of the supplier side. Samsung and SK Hynix aren’t trying to replace their American tools wholesale, TechInsights puts Chinese equipment at a 20 to 30 percent discount against the incumbents, and by Reuters’ account there’s no commitment yet to deploy AMEC gear at any real scale. What they’re building is optionality, a qualified backup they only need to reach for if maintenance on the Western tools ever becomes the actual chokepoint instead of the purchase itself.

The part I keep turning over is who’s doing this. Samsung and SK Hynix are the two companies that picked up the most ground while export controls slowed down China’s own memory makers. They aren’t the underdogs in this fight, they’re close to the companies the policy was partly designed to protect. And they’re the ones now hedging against the possibility that the same government turns the screws on them next, whether through a change in Washington or just the kind of annual-license uncertainty that’s already made them nervous enough to spend two years testing a workaround quietly. China’s own chip exports grew 88.7 percent even under the current restrictions, which should tell you how much room both sides still have to keep adjusting.

None of this shows up in a press release, which is exactly the point. The brand on your SSD or your phone’s memory chip was never a reliable guide to who actually made it, and now it isn’t even a reliable guide to what tools built it. I don’t know if Micron is running similar trials somewhere quietly. Nobody’s leaking that story yet. I’d be surprised if it isn’t at least on a slide deck in Boise.

Sources