LBO of Tethys with Abenex
Advised by Largillière Finance, Tethys, a specialist in pyromechanical systems for critical applications, welcomes Abenex as its new majority shareholder, alongside its management team and Bpifrance
Abenex has announced the acquisition of a majority stake in Tethys (revenues: €10 million), a specialist in pyromechanical systems for critical applications, alongside its shareholders, Istria Capital and Bpifrance. The objective is to accelerate Tethys’ development in France and internationally, across markets driven by increasing investment in the defense, space and energy sectors.
In this transaction, Largillière Finance acted as M&A advisor to the management team, Tethys’ shareholders and Bpifrance. This marks Largillière Finance’s fifth transaction in the aerospace and defense sector over the past 12 months, following the acquisition of Satys Cabin by UUDS Aéro, the LBO of Coraxes with Sodero and Cita, the sale of KEP Metal Solutions to Tikehau and Aciturri Aeroengines, and the MBO of UUDS Aéro with CAPZA.
Founded in 2004, Tethys has established itself as a recognized European player in the design, assembly and production of pyromechanical systems for defense, aerospace and security industry leaders such as MBDA, Naval Group, ArianeGroup and Safran.
Positioned in a niche market with high barriers to entry, and operating in a sector largely dominated by major groups, Tethys stands out through its status as an independent player, a source of agility and strategic attractiveness.
Driven by rising investment in defense, space and critical energy infrastructure, the pyromechanical devices market is experiencing sustained growth momentum. Tethys benefits from strong commercial visibility, supported by long-term programs generating recurring revenues and contracts frequently awarded on a single-source basis for periods ranging from 10 to 20 years.
With the support of Abenex and Bpifrance, Tethys intends to accelerate its growth strategy along several key pillars, notably through a significant expansion of its industrial capabilities via the extension of its production site, the development of business prospecting activities in France and across Europe, and the continuation of an active external growth strategy aimed at positioning Tethys as an independent European leader in pyromechanics.
The management team, led by Philippe Saussol, is also making a significant reinvestment alongside Bpifrance as part of the transaction.
2026
Largillière Finance Experts
- Paul Bougnoux
- Thomas Bureau
- Maxime Fournely
- Jean-Baptiste François
Counterpart
The arrival of Abenex marks a new phase of development for Tethys. Their operational approach, entrepreneurial DNA and ability to mobilize the right expertise were decisive factors in our decision. The Largillière Finance team was a highly committed partner from the initial reflection phase through to the selection process. Their deep understanding of both our company culture and the challenges specific to our market within the defense sector enabled them to introduce highly relevant potential investors.
Philippe Saussol
Chairman of Tethys
The Largillière Finance team is delighted to have supported the management team of Tethys and its shareholders, Istria Capital and Bpifrance, in this transaction in the defense sector, where we have recognized expertise. The implementation of an in-depth competitive process enabled us to identify a leading financial partner, perfectly aligned with management’s ambitions.
Paul Bougnoux
Chairman and Co-Founder of Largillière Finance
Largillière Finance, the independent M&A advisor for growth companies
As an independent specialist in mid-cap transactions, Largillière Finance advises executives and shareholders on their capital transactions, including disposals, acquisitions, LBOs, financing solutions (equity and/or debt), financial engineering (valuation, etc.) and financial strategy advisory.
With more than 45 investment bankers and professionals, a strong presence in Paris, across the French regions (Bordeaux, Lyon, Nantes) and internationally, Largillière Finance has completed nearly 400 transactions and established itself as a leading market player.
Largillière Finance is a member of REACH Cross-Border M&A, a global M&A advisory network specialized in the mid-market segment, bringing together more than 400 investment bankers across major financial centers in over 30 countries.
