• When the U.S. blacklisted six Chinese entities last month in response to a suspected spy balloon traversing the country, a little-known tech firm in Northern California had reason to pay particularly close attention.
• AXT Inc. has extensive ties to China that go beyond its manufacturing facilities there.
• The company owns an 85% stake in a Chinese subsidiary that produces materials for semiconductors and has counted as one of its biggest customers a giant state-owned defense firm linked to Beijing’s surveillance balloon program, according to AXT’s filing to the Securities and Exchange Commission in August.

Tagged: Balloons