Thermo Fisher Scientific offloads microbiology business to PE firm Astorg

The life sciences giant is divesting its global microbiology unit, which generated $645 million in revenue last year, to the pan-European private equity firm as part of an active portfolio management strategy. The transaction is expected to close in the second half of 2026.

Thermo Fisher Scientific has signed a definitive agreement to divest its global microbiology business to Astorg, a pan-European private equity firm, in a transaction valued at approximately $1.075 billion. The deal, announced on 27 April 2026, marks a significant strategic shift for the Massachusetts-based life sciences giant as it continues to actively manage its portfolio and redeploy capital.

The microbiology unit being sold encompasses antimicrobial susceptibility testing and culture media product lines, serving clinical diagnostics, pharmaceutical manufacturing, and food safety testing markets. The business generated $645 million in revenue during 2025 and currently operates as part of Thermo Fisher's Specialty Diagnostics segment. With approximately 2,400 employees and 13 manufacturing and research and development sites distributed globally, the unit represents a substantial operational footprint within the company's broader diagnostics portfolio.

Marc N. Casper, chairman and chief executive officer of Thermo Fisher Scientific, characterised the transaction as reflecting the company's active portfolio management strategy. "The transaction reflects our active management of the company and provides additional capital we can deploy to create shareholder value," Casper stated. He expressed confidence that the microbiology business would be an excellent fit within Astorg's portfolio and anticipated a smooth transition for both the business and its employees under new ownership.

For Astorg, the acquisition represents the tenth investment from its Astorg VIII fund and reinforces the firm's position as a leading investor in healthcare and life sciences. The Luxembourg-headquartered private equity house has deployed approximately €8 billion in the sector to date, including co-investments, representing roughly 40 per cent of its total portfolio. Astorg's healthcare investments include established platforms such as Solabia, Nexpring Health, CordenPharma, OPEN Health, Cytel, Clario, Nemera, and Echosens.

Astorg's strategic vision for the acquisition centres on transforming the microbiology business into an independent, privately owned platform with dedicated focus on accelerated growth and enhanced operational performance. The firm intends to partner closely with existing management to scale the business further, pursuing both organic growth initiatives and strategic mergers and acquisitions. This approach aligns with Astorg's proven track record in executing complex carve-outs and building specialised healthcare platforms with clear strategic direction.

The microbiology testing market is supported by several structural tailwinds that underpin the business's long-term prospects. Increasing infection complexity, progressively stringent food safety standards, and growing quality control requirements across the pharmaceutical industry are all contributing to sustained demand for microbiology testing solutions. These factors reinforce the critical role that microbiology testing plays in safeguarding public health across multiple sectors.

The transaction is structured to include cash consideration along with a $50 million seller note. Thermo Fisher anticipates closing the deal during the second half of 2026, subject to customary closing conditions and applicable regulatory approvals. Until completion, Thermo Fisher will continue to operate the business as usual, ensuring continuity for customers and employees throughout the transition period.

From a financial perspective, Thermo Fisher expects the transaction to be dilutive to adjusted earnings per share by $0.15 in the first full year following closure. The company has indicated it will provide comprehensive details regarding the expected impact on its 2026 financial outlook during its second quarter earnings call, allowing investors and analysts to assess the transaction's implications more fully.

The divestiture represents a significant supplier transition event for laboratories and organisations that rely on Thermo Fisher's microbiology products and services. Clinical laboratories, pharmaceutical quality control facilities, and food safety testing operations will need to monitor developments closely as the business transitions to independent ownership under Astorg's stewardship. The window between announcement and expected closure in the second half of 2026 provides stakeholders with time to prepare for any operational changes that may accompany the ownership transition.

This transaction continues a broader trend of portfolio optimisation among major life sciences companies, as they seek to focus resources on core strategic priorities whilst divesting non-core assets to specialised investors capable of providing dedicated attention and capital for growth. For Astorg, the acquisition offers an opportunity to build another scaled, specialised platform within its healthcare portfolio, leveraging its sector expertise and operational capabilities to drive value creation in the microbiology diagnostics space.

Source:

Thermo Fisher Scientific Signs Agreement to Sell its Microbiology Business to Astorg [Accessed April 29, 2026] https://ir.thermofisher.com/investors/news-events/news/news-details/2026/Thermo-Fisher-Scientific-Signs-Agreement-to-Sell-its-Microbiology-Business-to-Astorg/default.aspx