In September 2026, the LEGO Group launched a campaign celebrating something its fans have always known, that the bricks last. "Since their creation in 1958, LEGO bricks have been designed to be built and rebuilt," said its Chief Sustainability Officer, Annette Stube, placing durability at the heart of the company's sustainability story (Kania, 2026). The campaign cited a finding that about 74 percent of adults believe products should be built to last and used many times over. It is hard to disagree. A toy that passes from parent to child to grandchild is, on almost any measure, better than one that breaks by Boxing Day.

The circular economy literature agrees. Extending how long products stay in use is one of its oldest prescriptions, from the critique of the "throwaway society" (Cooper, 2005) to strategies that "slow" resource loops through durable design (Bocken et al., 2016). LEGO's own research suggests that 94 percent of UK families who part with their bricks give them away or sell them. By the standards of most consumer goods, the brick is a circular success.

And yet durability has a second face.

Permanence does not choose where it lands

For more than two decades, LEGO pieces from a container spill off Cornwall in 1997 have been washing up on English beaches. Studying them, researchers estimated that a LEGO brick in the marine environment could survive for up to 1,300 years (Turner et al., 2020). The same engineering that keeps a 1970s brick clicking neatly onto a 2026 set keeps it intact in the sea. Durability is indifferent to context. It does not distinguish between the playroom and the shoreline.

Time also changes what durability carries. A study of second-hand toys found that cadmium released from yellow and red LEGO bricks of the 1970s and 1980s exceeded today's EU toy safety limit by roughly an order of magnitude (Turner, 2018). A brick built to last also preserves the chemistry of the decade in which it was made.

A recent teaching case calls this LEGO's "durability paradox" (Lund University, 2026). The qualities that made the brand trustworthy, its safety, longevity and compatibility across generations, now sit alongside a growing "shadow inventory" of bricks in homes, landfills and oceans that will outlive everyone who bought them.

Why durability is a wicked problem

Policy tends to treat durability as an unambiguous good. In a study of the EU's strategy for sustainable textiles, Richardy and colleagues show how the assumption that longer-lasting products automatically deliver economic, environmental and social gains breaks down in practice (Richardy et al., 2025). Drawing on the idea of wicked problems (Rittel & Webber, 1973), they argue that durability is entangled with rebound effects, poorly understood terms and gaps in knowledge, so that solving one part of the problem reshapes the others.

LEGO illustrates this well. Durable bricks hold their value, and the secondary market is booming. Retired LEGO sets have been found to appreciate by around 11 percent a year on the secondary market, outperforming many conventional investments (Dobrynskaya & Kishilova, 2020). LEGO bought BrickLink, the largest marketplace for used bricks, in 2019. Durability has turned toys into assets.

Whether that is good for the planet depends on a question the circular economy often skips. Reuse and recycling reduce environmental impact only if secondary products actually displace new production, a problem known as the circular economy rebound (Zink & Geyer, 2017). If the second-hand market grows alongside new sales rather than instead of them, durability adds to the total stock of plastic rather than slowing its growth. LEGO's revenue rose 12 percent in 2025, so the reuse economy and the new-brick economy appear to be growing together.

Not a barrier, but a paradox

Why has a company with LEGO's engineering talent not simply solved this? A recent study of 18 manufacturers offers a useful answer (Robertson et al., 2026). Tensions rooted in materials, such as the tension between durability and recyclability, do not stay on the design table. They travel into the organisation as paradoxes of learning, belonging and organising (Smith & Lewis, 2011). Circular design, the authors conclude, is less a matter of removing barriers than of continuously managing tensions that will not go away.

LEGO's recent history reads like a case study of exactly this. In 2023 it abandoned its prototype brick made from recycled PET bottles, after concluding that it would not reduce emissions (Milne, 2023). Its take-back scheme, LEGO Replay, launched in 2019, is still described as a pilot, and the 2025 Annual Report says the company is still "testing" how to collect, clean and sort used bricks (LEGO Group, 2026). The Lund case describes this position as a "managed deadlock", in which new bricks fund circular experiments that never quite scale.

Paradox theory warns against forcing a premature choice between competing demands. It also carries a risk that deserves naming. Managing a paradox can become a comfortable place to stay, especially when the core business is thriving.

Where the paradox lands

The costs of durability are not evenly distributed. In much of the world, plastic is collected not by municipal systems but by informal waste pickers, who recover what has resale value and leave the rest (Wilson et al., 2006). Mixed, small, durable plastic toys rarely make the cut. In those places, a product designed to last for centuries becomes someone else's problem for centuries.

LEGO assessed pollution as not material in its 2025 sustainability statement. Extended producer responsibility rests on the principle that producers remain responsible for their products after sale (Lindhqvist, 2000). In practice, that responsibility tends to stop where formal collection systems end, which is exactly where the durability paradox becomes most acute.

Does LEGO Legacy answer the paradox?

In my LEGO case, I proposed a bridge called LEGO Legacy. It would offer certified pre-owned and heirloom sets, each with a set passport recording its year, owners and repairs, sold through BrickLink and LEGO stores, with a trade-in option for families and Replay for broken bricks. It is fair to ask whether it addresses the paradox or simply decorates it.

It fits the first half well. Legacy turns durability from a marketing claim into a service that keeps bricks in play, which is exactly what "slowing the loop" asks for (Bocken et al., 2016). It also gives LEGO a reason to measure second life through BrickLink data, something its reporting does not yet do. And because older bricks would pass through a certification step, it creates a natural point to screen for legacy chemicals such as cadmium (Turner, 2018), rather than leaving that risk with families.

It fits the second half poorly, and it carries risks of its own. A premium heirloom tier could deepen the collectible market, and higher resale values can make new sets easier to justify, feeding the very rebound it is meant to prevent (Zink & Geyer, 2017). A channel run by LEGO could squeeze the charities and independent resellers who already run much of the reuse economy. And Legacy does nothing for bricks that leave the loop in places without take-back, where the paradox is sharpest.

So Legacy is a necessary bridge, but not a sufficient one. To answer the paradox, it would need three companions. The first is a public indicator showing whether second-hand bricks displace new production. The second is a take-back route that works where formal waste systems do not, for example through waste-picker cooperatives paid enough to make collection worthwhile. The third is a clear statement of how far LEGO's responsibility extends once a brick leaves the playroom.

The durability paradox will not be resolved by a better material alone. It asks a harder question of every company that sells long-lasting goods. If your product will exist for a thousand years, for how many of those years are you willing to be accountable for it?

Novo, known as Novo Nordisk until its rebrand in September 2026, is plain about its own misses in its 2025 sustainability statement. Total greenhouse gas emissions rose 19 percent, and the report says so at the start of its sustainability statement. It reports that it missed its stress target, that its aspiration for women in senior leadership was not met, and that its shareholder-elected board did not meet the Danish Gender Balance Act (Novo Nordisk, 2026). At a time when the EU's Omnibus reforms give companies room to say less, that candour deserves credit.

Candour, however, is not the same as comparability. A reader who wants to know whether Novo is moving towards its goals needs more than an honest account of this year. They need to be able to follow the same numbers, measured the same way, across years. That is where the 2025 statement becomes harder to read, for reasons that have less to do with intent than with growth.

Talk, action and the space between

Research on sustainability reporting offers two ways of reading a report like this. One sees ambitious statements as "aspirational talk" that can pull an organisation towards its goals, even before practice catches up (Christensen et al., 2013). The other warns that reports can become façades, managing the gap between what a company says and what it does rather than closing it (Cho et al., 2015). Studies of disclosure quality add a third point, that more information does not automatically mean better information, since what matters is whether a reader can use it (Michelon et al., 2015).

Novo's statement sits closer to the first reading than the second. But the third point is where its weaknesses lie. The information is there. It is simply spread across footnotes, rule changes and redefinitions in a way that leaves the reader to reconstruct the story.

When acquisitions move the numbers

In 2025, five newly acquired production sites explain much of what moved. Scope 1 and 2 emissions rose 81 percent against a target of zero by 2030. The renewable share of energy fell from 66 to 57 percent. Acquired sites accounted for over 80 percent of the waste sent to landfill and much of the 15 percent rise in water withdrawal (Novo Nordisk, 2026).

None of this is a failure of strategy. Growth through acquisition is a deliberate choice, and integrating new sites takes time. It is, however, a failure of visibility. When acquired and organic performance are reported as one figure, a reader cannot tell whether the company's own sites are improving while new ones catch up, or whether the whole system is moving the wrong way. Each acquisition quietly resets the baseline.

Numbers that change after the fact

At least eight 2024 figures were restated in the 2025 report, from the Scope 3 base year to the renewable energy share and the plastic footprint. The definition of zero landfill was refined to allow up to 0.05 percent of waste, and performance still came in at 0.06 percent. In the EU Taxonomy, the 2025 figure for aligned investment matches the 2024 headline of 6 percent, but the 2024 figure excluded a major acquisition, and in 2025 Novo adopted simplified rules early, which changed what was counted (Novo Nordisk, 2025, 2026).

Each change is explained, and most are signs of better data. Novo itself notes that future restatements of Scope 3 "remain plausible". The problem is cumulative. Research on highly rated sustainability reports has shown how easily a polished report can drift away from the events a reader most needs to understand (Boiral, 2013). Novo's report does not hide its changes, but scattered across footnotes they ask the reader to do the reconciling.

Spend is not carbon

Purchased goods and services make up 55 percent of Novo's Scope 3 emissions. Where the weight of what is bought is unknown, emissions are estimated from what is spent. Under that method, buying more shows up as emitting more, whatever suppliers achieve, and a supplier that cuts its own emissions may not show up in Novo's numbers at all. Research on corporate carbon data shows how much reported figures can diverge depending on the methods and sources behind them (Busch et al., 2022).

Novo says its goal is to use supplier-specific emission factors for much of its Scope 3 reporting. The missing step is to show progress towards that goal, by reporting each year how much of its largest emissions category rests on supplier data rather than spending.

Materiality on a calendar

The most delicate question concerns people. In 2025 Novo cut around 9,000 positions, and employee turnover rose from 5.5 to 18.4 percent. In the same year, its double materiality assessment listed "secure employment" among topics that are not material, and descoped severe human rights impacts for its own workforce, describing these as minor refinements (Novo Nordisk, 2026).

There may be good technical reasons. The assessment runs on an annual cycle, and the report does not say whether it was finalised before or after the September reorganisation. But that is exactly the point. Double materiality is meant to capture the impacts a company has on people, and a calendar cycle cannot always keep pace with decisions that change those impacts mid-year.

What a reader needs

None of this calls for new principles. It calls for a few tools that fit the processes Novo already runs.

1. A restatement log in one place, showing each changed figure, its old and new value, the reason, and its effect on any target.
2. A target tracker listing every target as met, missed, revised or discontinued, with dates and reasons.
3. A Taxonomy bridge that separates rule changes and acquisitions from real progress. Being Taxonomy-aligned means an activity meets the EU's technical criteria for environmental sustainability, not simply that it appears on the EU's list, so readers need to see which of those changed.
4. Day One Disclosure for acquisitions, reporting acquired sites separately for two years with a date by which each meets group standards.
5. An event-driven materiality check, so that a restructuring or acquisition above a set size triggers a re-test of the topics it affects.

As regulatory pressure eases, disclosures like these will survive only if companies find them useful. They should. A credible sustainability statement lets a reader see why the numbers moved, even when they moved the wrong way.