Thermo Fisher Scientific to Sell Microbiology Business to Astorg
Posted on 29 Apr 2026
Thermo Fisher Scientific has signed a definitive agreement to sell its microbiology business to Astorg for approximately $1.075 billion, comprising cash and a $50 million seller note. Announced on April 27, 2026, the transaction involves assets within Thermo Fisher’s Specialty Diagnostics segment. The microbiology business generated $645 million in revenue in 2025.
The divested portfolio provides antimicrobial susceptibility testing (AST) and culture media solutions used in clinical, pharmaceutical and food safety testing. These offerings are currently housed within Thermo Fisher’s Specialty Diagnostics segment. No additional product-level information was disclosed.

Thermo Fisher expects the transaction to close in the second half of 2026, subject to customary closing conditions and applicable regulatory approvals. The company stated the sale is expected to be dilutive to adjusted earnings per share (EPS) by $0.15 in the first full year following close. Thermo Fisher plans to provide further detail on the expected impact to its 2026 financial outlook during its second-quarter earnings call.
“The transaction reflects our active management of the company and provides additional capital we can deploy to create shareholder value,” said Marc N. Casper, chairman and chief executive officer of Thermo Fisher. “We believe the microbiology business is an excellent fit within Astorg’s portfolio. We are confident in a smooth transition and wish the business and colleagues continued success after close under its new ownership.”







