All four of the world's biggest chipmakers have now committed to buying ASML's most advanced chipmaking machine, which is very good news for ASML and for the AI chip race.

• TSMC, Samsung and SK Hynix all said they will use ASML's High-NA EUV machines, joining Intel, which already has them.
• Each machine costs about $400 million, making them the most expensive tools in chipmaking.
• Samsung and SK Hynix plan to use them from 2028 to mass-produce advanced memory chips for AI.
• Demand is strong enough that ASML may have to expand production capacity beyond its already-raised targets.
• The four chipmakers are also working with ASML on bigger 12-inch photomasks, which should lift output from these machines by 40%.

Outlook: ASML's stock, already up sharply over the past year, is expected to keep climbing as orders for the new machines build through 2028.