Decree No. 2026-302 of 21 April 2026 — Articles R. 311-5, R. 77-16-2 and R. 77-16-3 of the French Code of Administrative Justice

Published in the Official Journal on 22 April 2026 and applicable to administrative acts adopted from 1 July 2026 onwards, Decree No. 2026-302 fundamentally reconfigures the litigation regime for so-called "strategic" projects: onshore wind farms, ground-mounted solar PV of at least 5 MW, hydro of at least 1 MW, methanisation, geothermal energy, grid connection facilities, transport infrastructure, and certain industrial and agricultural projects. For the wind and renewable energy sectors — where operators have long suffered from lengthy and unpredictable litigation — the reform combines four major levers: removal of the two-tier court system, notification of the action within fifteen days on pain of inadmissibility, neutralisation of the time-extending effect of administrative appeals, and automatic "crystallisation" of legal grounds at two months. Operational overview for developers, operators and local authorities.

A reform that reaches well beyond onshore wind

Until 30 June 2026, the jurisdiction of the Administrative Courts of Appeal (CAA) at first and last resort over onshore wind disputes was a targeted regime, created by the decree of 29 November 2018 and later extended, by the decree of 29 October 2022, to ground-mounted PV of at least 5 MW. This derogatory regime had been designed for two specific sectors particularly exposed to long-running litigation.

Decree No. 2026-302 of 21 April 2026 completely rewrites Article R. 311-5 of the Code of Administrative Justice and converts that regime into a generalised system. The new scope covers, in addition to onshore wind without a power threshold: all "decarbonised energy" projects (ground-mounted PV of at least 5 MW, hydro of at least 1 MW, methanisation excluding wastewater plants, geothermal energy, sustainable aviation fuels), associated grid connection facilities, certain transport infrastructure projects above €5 million HT subject to environmental assessment, agricultural and industrial projects relating to food, economic and industrial sovereignty, and projects located within national interest operations and major urban planning operations.

The material scope is also broad: covered are not only "classic" environmental authorisations but all administrative acts — authorisations, refusals, extensions, transfers — that condition, even partially, the construction, completion, commissioning, operation, modification or extension of the projects concerned and their related works. Damages claims and contractual acts remain excluded and continue to follow ordinary rules.

The end of the two-tier court system

This is the most structural change. Under the new wording of Article R. 311-5, the Administrative Courts of Appeal have jurisdiction at first and last resort. The first-instance administrative tribunal is entirely bypassed, and the appeal layer before the CAA disappears, since the CAA acts as the final court on the merits.

In practical terms, a refusal of a building permit for a wind farm or for a 10 MWc PV installation must now be challenged directly before the territorially competent CAA, rather than before the administrative tribunal. A cassation appeal before the Conseil d'État remains available but is limited to points of law. The two-tier system, a guiding principle of French administrative litigation, is therefore suspended for this category of disputes.

For developers and operators, the consequences are significant. On the one hand, the risk of reversal on appeal disappears, securing favourable decisions. On the other hand, the first-instance procedure becomes strategically decisive: the full set of grounds, evidence and arguments must be deployed at once, with no possibility of "catching up" with an insufficient case on appeal. The choice of legal team, the quality of the technical expertise mobilised and the anticipation of opponents' arguments become decisive as soon as the initial application is filed.

Notification of the action on pain of inadmissibility

The second major lever: the requirement for the claimant to notify the action to the beneficiary of the challenged decision. The notification must be sent within fifteen working days from registration of the action, by registered letter with acknowledgment of receipt. The sanction is immediate and stark: outright inadmissibility of the action.

For opponents of a project, this procedural requirement imposes calendar discipline that materially changes the game. An action filed at the last minute within the two-month limit following publication of the contested decision must, within fifteen days thereafter, be formally notified to the beneficiary — which presupposes precise identification of the legal entity holding the authorisation and its official address. Any error — wrong addressee, wrong address, late notification — triggers inadmissibility.

For developers, this rule has a structural effect: it ensures that the existence of a dispute becomes known rapidly and with certainty. The period of post-decision uncertainty is significantly reduced, securing investment decisions, construction schedules and contractual negotiations with suppliers, lenders and offtakers.

End of the time-extending effect of administrative appeals

The decree introduces a new Article R. 77-16-2 of the Code of Administrative Justice under which "the limitation period for litigation against acts falling within the scope of Article R. 311-5 is not extended by the exercise of an administrative appeal".

This provision breaks with a central principle of French administrative litigation: since the origin of the action for excess of power, a gracieux or hierarchical administrative appeal lodged within the two-month limitation period suspended the litigation clock, which restarted only upon the express or implied decision of the administration. This mechanism is now neutralised for strategic projects.

For opponents, the consequence is direct: an administrative appeal to the prefect no longer "freezes" the litigation clock. To preserve their right to bring a contentious action, claimants must file within the initial two-month limit, regardless of any administrative appeals they may also pursue. The parallel pursuit of contentious and administrative remedies becomes the norm.

For developers, the rule mechanically restricts the tactical use of administrative appeals as a "purge" tool. It also tightens the legal-risk horizon: beyond the two-month period following the decision, the project is no longer exposed to a contentious action not yet brought, save very limited cases (e.g., defective notification).

Automatic crystallisation of grounds at two months

By amending Article R. 611-7-2 of the Code of Administrative Justice, the decree extends automatic crystallisation of legal grounds to the entire scope of the new Article R. 311-5. In concrete terms, parties may no longer raise new grounds beyond a two-month period from the communication of the first defence brief. Any ground raised thereafter is automatically dismissed without examination on the merits.

This extension consolidates a logic already established in wind litigation — recent case law, including the Nantes CAA ruling of 12 July 2024 (no. 22NT01245), already penalised claimants who provided the precision necessary to assess their grounds only after the two-month deadline. The rule now applies to all parties.

The strategic effect is considerable. Within the initial application and within the two months following communication of the first defence brief, claimants must deploy their full case: external legality grounds (lack of competence, procedural defects, lack of reasoning), internal legality grounds (error of law, error of assessment, landscape or biodiversity impacts, heritage impacts), planning law grounds, environmental law grounds, energy law grounds. Any ground raised later is dismissed.

For project defence, crystallisation is a first-order asset. It allows early identification of the full litigation perimeter and enables the defence to operate within a definitively fixed framework. It reduces exposure to "surprise grounds" developed late in proceedings, often in light of evidence produced by the defendant. Conversely, it raises the bar for the drafting of the first defence brief, the quality of which directly determines the crystallisation effect.

A ten-month decision deadline… but indicative

The new Article R. 77-16-3 I of the Code of Administrative Justice provides that "for disputes governed by Article R. 311-5, the Administrative Court of Appeal shall rule within a ten-month period from registration of the application". Where the CAA stays proceedings to allow the contested act to be cured, it has a fresh six-month period from the receipt of the curative brief.

The decree marks an important break, however, with the prior regime applicable to PV projects and methanisers: missing the deadline no longer triggers any automatic procedural sanction — in particular, it no longer transfers the case to the Conseil d'État. The ten-month period is now a piloting objective addressed to the courts, not a procedural guarantee offered to litigants. The claimant cannot invoke a missed deadline to accelerate the case; nor can the claimant obtain annulment of the administrative decision on the ground that the judge took too long.

In practice, the actual reach of the "target deadline" will depend on the internal case management of the CAA and on the human resources allocated to these technically complex files.

Operational implications for developers and operators

For wind, solar, hydro, methanisation and geothermal operators, Decree No. 2026-302 reshapes contentious strategy around four operational priorities.

Secure the upstream administrative phase. Environmental authorisations and building permits — the project's key decisions — will now concentrate all litigation risk within a tighter procedural framework. The quality of the application file, the robustness of impact assessments, prior public consultation and the detailed reasoning of favourable decisions take on critical importance. Any procedural or motivational flaw becomes an immediate attack point before the CAA.

Prepare the defence from the moment the decision is issued. First-and-last-resort proceedings before the CAA, combined with two-month crystallisation, require the legal team and technical experts to be mobilised as soon as the authorisation is delivered. Pre-built defence dossiers — structured arguments on each potential ground, technical expertise (landscape, biodiversity, acoustic, grid connection), applicable case law — become standard practice.

Identify actions quickly. The fifteen-day notification requirement on pain of inadmissibility ensures developers learn of disputes very quickly. The beneficiary must, however, be in a position to identify without delay the nature, scope and claimants of notified actions. An internal protocol for receipt and tracking of such notifications is now indispensable.

Align litigation strategy with financial strategy. The reduction of litigation uncertainty, the ten-month decision horizon and the removal of the two-tier system change the projects' risk profile and, consequently, their financing conditions. Negotiations with banks, infrastructure funds and offtakers must take these new parameters into account.

Conclusion: a new standard for strategic projects

Decree No. 2026-302 of 21 April 2026 marks a defining step in the legal stabilisation of strategic projects in France. For the wind energy sector in particular, which suffered from a litigation exposure that was both long and uncertain, the combination of a single court, accelerated crystallisation, mandatory notification and removal of the time-extending effect constitutes a paradigm shift.

COTEG supports developers, operators, investors and local authorities throughout the full lifecycle of these projects: securing administrative authorisations, defending contentious actions before the Administrative Courts of Appeal, negotiating project finance, managing power purchase agreements, and advising on portfolio acquisitions and divestments of energy assets. In a procedural environment now significantly tightened, the anticipation and coordination of legal, technical and financial expertise make all the difference.

Author: Jerome Bouyssou-Savart, Partner — Business Litigation, Wind Energy, Food & Agribusiness.

This article is published for information purposes only and does not constitute individualised legal advice. The above developments reflect the state of French law as of 15 June 2026.