's board on Tuesday named as the DNA sequencing company's as it tries to rebound from a grinding dispute over its acquisition of cancer test developer Grail.
Thaysen, a 48-year-old longtime executive at medical devices firm , will step in as CEO on Sept. 25. His nomination comes months after a bitter with activist investor ended with Illumina's former CEO, Francis deSouza, despite securing enough votes to stay.
Illumina closed its of Grail in 2021 without first securing approval from antitrust regulators in the U.S. and European Union — a decision that prompted Icahn to seek board seats and push the companies to unwind the deal.
Shares of Illumina fell more than 4% on Tuesday after the announcement.
New leadership could help Illumina regain its footing after a rocky past two years. The company's market value has fallen to roughly $25 billion from around $75 billion in August 2021, the month it closed its acquisition of Grail.
Thaysen will step in as Illumina fights seeking to block the Grail acquisition: One from the European Commission, the EU's executive body, and another from the U.S. Federal Trade Commission.
Illumina has appealed both orders and expects final decisions in late 2023 or early 2024.
Thaysen will join Illumina after a nearly 10-year tenure at Agilent. He led the analytical instruments division of Agilent since 2018, and served as president of the company's diagnostics and genomics department from 2014 to 2018.
He nearly doubled that division's operating profit during those four years, according to a press release from Illumina.
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"Jacob's unique combination of deep technological and commercial experience will be a great addition to Illumina," Stephen MacMillan, the chair of Illumina's board, said in the release. "He brings a fresh perspective, a demonstrated track record driving profitable growth, and a strong commitment to create value for all of Illumina's stakeholders."
Thaysen will take over for Charles Dadswell, who has been serving as Illumina's interim CEO since June. Dadswell will resume his role as senior vice president and general counsel at Illumina.