Every answer and its explanation appears here once you have finished the path. Each one then links to the matching glossary entry, where the concept is set out in full with its worked example.
1. Between March and June 2023, almost every founding member of the Net Zero Insurance Alliance left one after another, citing a legal risk rather than disagreement with the goal. Which risk?
Antitrust risk, competitors coordinating underwriting commitments
The alliance gathered commitments to align underwriting portfolios with a net zero trajectory, on the model of similar investor coalitions. The trigger for the departures is documented and is not climatic: several US state attorneys general threatened antitrust action against coalitions gathering competitors around coordinated commitments, and members judged that risk out of proportion to the reputational benefit of membership. The episode teaches a structural fragility of voluntary commitments coordinated between direct competitors, and it must be put exactly: what gives such a commitment its force, the fact that competitors hold to it together so that none loses business by observing it, is precisely what exposes it to the charge of concerted practice. One cannot have both, and an underwriting alliance is more vulnerable than an investor one, because refusing to cover is a refusal to sell. The practical consequence since is that commitments have largely migrated from the collective to the individual, where they are less effective but legally tenable.
Glossary entry · retrait-nzia2. In January 2023, a joint investigation by several newsrooms concluded that more than ninety per cent of the avoided-deforestation credits examined, certified by the voluntary market's main body, probably corresponded to no real reduction. What does that do to the companies that had bought them?
Their neutrality claims become a legal risk instead of an argument
A voluntary-market credit lets a company offset part of its emissions by funding a project meant to avoid or sequester them elsewhere, and its entire value rests on a baseline: what would have happened without the project. That baseline is what the investigation put in question for avoided deforestation, showing it was built on largely overstated clearing assumptions, so that the reductions sold were mostly fictitious. The consequence for buyers is a complete reversal in the meaning of their communications, and that is the point to hold: a company, several insurers among them, that had announced carbon neutrality resting partly on such credits finds it has publicly asserted something that did not happen. The commercial argument becomes an exposure, on misleading advertising first and liability after. What a professional should draw from this goes beyond carbon: a commitment whose verification is delegated to a third party is no more solid than that third party's method, and the buyer stands alone before the public it addressed.
Glossary entry · credibilite-credits-carbone3. An environmental organisation files a complaint with the UK advertising regulator against a London insurance market, challenging its climate communications against its continued underwriting of fossil risks. What does this kind of action make enforceable?
Consistency between what is publicly announced and what the books actually carry
Greenwashing in insurance means the gap between publicly communicated climate commitments, neutrality, coal exit, alignment with a trajectory, and the real content of underwriting and investment portfolios, where that gap arises from misleading communication rather than mere delay in execution. The distinction between the two is the heart of the matter, because it decides what is culpable: nobody demands that an insurer have already reached its target, and a transition plan running late is not deception. What becomes enforceable is that what it says match what it does at the moment it says it. The lever used deserves understanding, since it is not the expected one: neither the prudential supervisor nor a climate court, but advertising law, whose standard is the truthfulness of a message addressed to the public rather than environmental performance. It is therefore far quicker to use, requires no demonstration of harm, and produces a public decision documenting the gap. This is why the exposure is real long before any climate litigation concludes.
Glossary entry · greenwashing-assurance4. Several European reinsurers stop covering new thermal coal mines. Part of the capacity redeploys towards less demanding markets. What follows about the effect of these policies?
Risk can move without shrinking, which the exiting book does not show
An exclusion policy is the most visible instrument of sustainable underwriting: a formal commitment to stop covering thermal coal activities beyond defined thresholds, often extended to tar sands, the Arctic and oil and gas expansion. Its real effectiveness is debated, and the reason for the debate is the question itself: the withdrawal of large Western carriers can be offset by alternative capacity in less demanding markets, in which case the project finds cover elsewhere and proceeds anyway. What makes the subject hard is that the exiting party's book shows sincere, measurable, reportable progress, while the effect on the real world depends on what happens at others, out of its sight and off its returns. Two honest readings therefore coexist: exclusion makes coal financing dearer and more awkward, which is not nothing; it does not end it, and presenting an exit from a portfolio as an emissions reduction is exactly the slide the previous question penalises. A practical difficulty follows, the highly variable granularity of these policies, which makes comparison between firms unreliable.
Glossary entry · politique-exclusion-charbon5. Under the European sustainability reporting directive, an insurer must report two different things. Which?
How climate threatens its portfolios, and how its portfolios bear on the climate
Double materiality is the guiding principle of European sustainability reporting, and its name says exactly what it requires: looking at the company from two viewpoints that do not reduce to one another. Financial materiality captures how sustainability matters affect the company's value, cash flows and risks, and it is the familiar reading, the one an insurer already practises when assessing its natural catastrophe exposure. Impact materiality captures how the activity affects the environment and society, regardless of any financial consequence for the company, and it is the new one: it asks for the reporting of something that appears in no balance sheet line. For an insurer, this means reporting both what climate does to its book and what its underwriting and investments do to emissions. It is also what distinguishes the European approach from historically more financial frameworks. Note that the boundary between the two is moving rather than watertight, a serious enough negative impact generally becoming a financial risk in the end, with a lag that is precisely where the subject lies.
Glossary entry · double-materialite6. An oil company sees part of its reserves become unusable under a constrained carbon budget. What makes that risk hard to provide for, for an institutional investor?
Its discontinuity: the write-down comes from a shock of unknown date, not gradual erosion
A stranded asset suffers premature write-down, loss of value or conversion into a liability under the transition: hydrocarbon reserves unusable within a constrained carbon budget, a thermal plant made unprofitable by carbon pricing, infrastructure incompatible with new standards. For an insurer the risk is twofold and must be seen on both sides of the balance sheet: it threatens the value of its investments, and the solvency of those insureds exposed to it. What makes it hard to provide for is not its size but its shape in time. Gradual erosion can be forecast, amortised and smoothed; stranding proceeds from a regulatory, technological or market shock of unknown date, whose effect is immediate on the day it lands. One can therefore be right on the substance for years while being entirely wrong on the timing, which is the worst configuration for reserving. It is precisely this discontinuity that gave rise to climate stress testing: failing to know when, one looks at what the shock would do if it came, which is an admission of method as much as a tool.
Glossary entry · actifs-echoues7. A sovereign green bond is issued at a yield slightly below its conventional equivalent. What is the limit of that gap, for an insurer running a large bond portfolio?
It is small, volatile and empirically contested, so thin to trade on
The greenium is the favourable yield gap enjoyed by certain transition-aligned assets, a green bond being able to fund itself slightly below an equivalent conventional bond. The brown discount is its mirror: the valuation penalty applied to carbon-heavy assets, reflecting the market's anticipation of transition and stranding risk. These gaps are interesting because they show climate risk being progressively priced into assets, meaning the moment a concern becomes a financial datum. Their limit is that they remain small, volatile and empirically contested: studies agree on neither their size nor their persistence, and part of the observed gap may come from differences of issuer, maturity or liquidity rather than from the label. For an insurer running a large bond portfolio, the trade-off is therefore between current yield and transition exposure, on a price signal too thin to settle it alone. There is besides a paradox worth holding: too large a greenium would signal that the green asset is expensive, not that it is safe.
Glossary entry · prime-verte-decote-brune8. A coastal region sees its flood exposure grow faster than its sea defences and its prevention budget. How does that show up in insurance?
The protection gap widens, and the territory drifts out of market terms
The adaptation gap measures the distance between a territory's needs in the face of already unavoidable climate impacts and the financial, technical and institutional means actually mobilised. It differs from mitigation, which aims to cut emissions: adaptation aims to reduce vulnerability to what will happen anyway. Its insurance translation is direct and should be named plainly: where exposure grows faster than the capacity to prevent and to transfer, territories become progressively uninsurable on market terms, and the protection gap widens. The insurer's position there is twofold and uncomfortable, which is the real subject of the question. It plays a signalling role, since its price reveals rising risk before the public sees it, and that is useful information which can trigger prevention spending. But the same signal, pushed to its conclusion, is a withdrawal, and it strikes first the most exposed and least resourced territories, particularly in developing countries. Telling the risk and continuing to carry it then become two requirements that do not point the same way.
Glossary entry · ecart-adaptation-climatique9. Launched in 2018 in the Mexican state of Quintana Roo, funded by a hotel tax and taken out by a conservation fund, the first parametric coral reef policy pays on a wind speed threshold. What does the parametric form solve here that an indemnity policy could not?
The lack of a surveyable asset value, and the urgency of repair
Indemnity cover presupposes an asset whose value can be established and whose damage can be quantified, and a reef is not one in the property sense: its economic value lies in indirect services, coastal protection against erosion and flooding, support to fishing and tourism, which no survey converts into an amount after a cyclone. The parametric trigger sidesteps the obstacle by resting on wind speed recorded over a defined zone, which makes payment both possible and beyond argument. The second reason is timing, and it is specific to the object: broken corals must be fixed within days of the storm to re-fuse, so an indemnity paid after months of survey would be accurate and useless. The full structure deserves a look, because it answers the question such a policy prompts: the policyholder is not an owner, no title applying to a reef, but a conservation body, and the funding comes from a hotel tax, meaning the businesses that live off the beach the reef protects. The chain holds end to end, and that is what makes it a teaching case rather than a curiosity.
Glossary entry · assurance-parametrique-recifs