Meridiam Brand Guidelines: Thierry Déau’s 2005 Paris Firm, SUEZ & a Mission Status

A former project developer and his own fund.

Meridiam was founded in Paris in 2005 by Thierry Déau, who, French Wikipedia says, had been managing director of Egis Projects, the Caisse des Dépôts subsidiary that developed, financed and managed infrastructure projects. English Wikipedia says the new firm was set up to finance public infrastructure and to give long-term savings a secure investment framework, with financial and operational support from the Crédit Agricole group and the engineering company AECOM.

Its first fund, Meridiam I, had its first closing in 2006, and that year the firm took on its first two projects: the Limerick Tunnel in Ireland, which opened in July 2010, and the A5 motorway in Austria, opened in January 2010, according to both Wikipedias. In 2007 it took on the Fulcrum LIFT local health-facilities project in the United Kingdom. Motorways in Germany, Poland and Slovakia followed in 2008 and 2009, along with the velodrome at Saint-Quentin-en-Yvelines and, in the United States, the Port of Miami Tunnel, inaugurated in May 2014, and the North Tarrant Express in Texas, opened in October 2014.

In 2012 Meridiam set up a new supervisory board and changed its ownership so that the majority of its shares were held by partners and employees, English Wikipedia says; it records that AECOM still held 30 per cent in 2013. Déau remains founder and chief executive, the company says, and English Wikipedia describes the firm as a specialist in developing, financing and managing long-term public infrastructure projects.

Concessions, Africa and a share of SUEZ.

Much of Meridiam’s record is a list of public–private partnerships and concessions. English Wikipedia names the Montreal University Hospital Research Centre and the Long Beach Courthouse in California, both opened in 2013; the second phase of Nottingham Express Transit, running from May 2015; and the South Europe Atlantique high-speed line in France, which opened in July 2017. In February 2015 it signed the concession joining the ports of Calais and Boulogne-sur-Mer, which included the Calais Port 2015 extension, completed in May 2021.

From 2014 it raised a fund dedicated to Africa, opened an office in Istanbul and, in 2016, another in Dakar. French Wikipedia records a 40 per cent stake in Setrag, the operator of the Transgabonais railway in Gabon, taken in September 2021, and a contract signed in March 2022 for electric buses in Dakar. Closer to home, Meridiam bought the Dutch electric-vehicle charging operator Allego on 31 May 2018, both Wikipedias say, and in September 2023 it acquired Okamac, a refurbisher of Apple products, French Wikipedia adds. In January 2024 it increased its holding in the Terminal B project at LaGuardia Airport in New York.

Energy projects form a growing share. In October 2020, English Wikipedia says, Meridiam became the majority shareholder of Voltalis, a French company that manages household electricity use; in December 2020 it concluded, with Vinci, the public–private partnership for the D4 motorway in the Czech Republic; and at the end of September 2021 it launched, with Hydrogène de France and SARA, the West Guyana Power Plant project in French Guiana, which stores intermittent renewable energy using hydrogen.

The largest single step was into water and waste. With Global Infrastructure Partners and the Caisse des Dépôts group, Meridiam formed the consortium that bought the “new” SUEZ after Veolia’s takeover of the original company. Wikipedia gives the split as 40 per cent each for Meridiam and GIP and 20 per cent for the Caisse des Dépôts with CNP Assurances, and SUEZ announced in February 2022 that the consortium had finalised the acquisition on 31 January 2022. Meridiam’s own figures, at the end of 2025, count SUEZ and Allego among assets spread across 58 countries.

How infrastructure investors present themselves.

Infrastructure investors sell something hard to picture: long-term ownership of things other people use every day. Their websites therefore lean on the assets themselves. Macquarie Asset Management’s pages open on named portfolio companies, from a New Zealand telecoms provider to an onshore wind farm in north-eastern Brazil, and Brookfield Infrastructure sorts its portfolio into utilities, transport, midstream and data, with ports, railways, toll roads and pipelines named as the things it owns and runs.

The language is consistent too. Brookfield Infrastructure speaks of “critical infrastructure” and long-life assets with contracted and regulated revenues; Macquarie Asset Management says it seeks results “over the long term.” Responsible-investment wording sits alongside it: Macquarie’s purchase of the former UK Green Investment Bank in 2017, renamed Green Investment Group, came with a green “special share” held by independent trustees, according to the UK government’s announcement of the sale.

Listed vehicles add another layer of documents. Brookfield Infrastructure publishes quarterly results, supplemental information, letters to unitholders and investor-day presentations, and in 2026 it set out a plan to fold its two listed securities into one. Parent groups publish annual reports and history timelines; Macquarie’s runs from a three-person Sydney office in 1969 to the motorway deal of 1994 that it calls the start of its infrastructure business.

Trade rankings are part of the picture. Infrastructure Investor’s II 100 list of managers placed GIP, by then part of BlackRock, at the top in November 2024, and noted that Macquarie, first in every earlier edition, had dropped to fourth. This guide sets out what can be checked about each firm — who founded it, who owns it and how it presents its portfolio — and marks clearly what rests only on the company’s own word.

A mission written into the by-laws.

Meridiam’s identity rests on purpose. The company says it wrote its mission — delivering sustainable infrastructure that improves the quality of people’s lives — into its by-laws, and adopted France’s société à mission, or mission-driven company, status in 2019. It then sought B Corp certification, which it says it obtained in 2022; French Wikipedia dates the certification to December 2022. A Mission Committee that includes independent members monitors the impact of its investments and reports to the supervisory board, the company says.

It lists other formal markers too. The company reports ISO 9001 certification of its investment process since 2012 and ISO 37001 anti-bribery certification since November 2021, extended to more offices in 2023 and 2025, and English Wikipedia notes that it has been a signatory of the UN Principles for Responsible Investment since 2010. It sorts its work under three headings — critical public services, sustainable mobility and innovative low-carbon solutions — and frames them against the UN Sustainable Development Goals. It says it employs about 400 people in ten offices, from Paris, Luxembourg and Vienna to Washington, Istanbul, Amman, Dakar, Addis Ababa, Libreville and Johannesburg.

For a design guide, Meridiam shows how a fund manager can lead with mission language and named public works rather than with financial figures. Compare GIP, its partner in the SUEZ consortium, and Ardian, another Paris investor. For this guide we use a deep forest green, a pale sage and a sand with a serif, an unofficial interpretation; no product or logo is reproduced.

Keep Meridiam’s identity on hand — save it to a board in the Made Good inspiration library.