Carl Icahn Hits Illumina Board With Sealed Suit in Delaware (1)

Carl Icahn sued Illumina Inc.'s former CEO and members of its board Tuesday, about six weeks after saying the biotech company and its new CEO have his “full support.”

Several of Icahn’s companies filed the lawsuit under seal in Delaware’s Chancery Court four days after European regulators ordered the DNA-sequencing giant to unwind its greater than $7 billion acquisition of the cancer-detection company GRAIL.

Details of the filing weren’t immediately available thanks to a court rule letting legal complaints remain confidential for five days while the two sides propose redactions.

The billionaire activist investor opened the new front about five ...