Elon Musk was the bearer of bad news for Intel over the weekend—and the chip manufacturer’s red-hot stock was taking a hit on Monday as a result.

Intel shares slid 4.5% to $113.92 ahead of the opening bell. They were up 25% over the one-month stretch through Friday’s close.

The stock looked set to snap its good run after Musk signaled that Intel rival Taiwan Semiconductor Manufacturing Co. was exploring how to help his chip venture Terafab run its Texas semiconductor factories.

“Just discussions, but something may come of it,” Musk wrote in a post on his social-media site X, in response to a report saying TSMC and Terafab were in talks.

TSMC’s U.S. shares climbed 1% in Monday’s premarket.

Investors had been hoping Intel would have Terafab all to itself. Intel joined the project, which also includes Musk-led companies SpaceX and Tesla, in April. The stock surged 114% that month thanks to a slew of deal announcements.

Still, the talks with TSMC don’t have to be too much of a blow for Intel. Musk signaled in a follow-up reply on X that TSMC could supplement rather than replace Intel’s role in the semiconductor manufacturing plant, which aims for 1 terawatt of compute production a year.