A Year Older, A Year Wiser (and Farther from Frontier): Invention Rents and Human Capital Depreciation

GAICIL Insights

Age discrimination in the innovation economy may be a measurement error.¹ A Year Older, A Year Wiser (and Farther from Frontier): Invention Rents and Human Capital Depreciation, by Philippe Aghion, Ufuk Akcigit, Ari Hyytinen and Otto Toivanen, examines how an invention's arrival affects the wages and employment of the inventor's white-collar and blue-collar co-workers. Innovation creates winners and losers, and the distribution of benefits within firms is poorly understood. The authors merge individual income data, firm-level data and patenting data in Finland over 1988-2012, using a conditional difference-in-difference approach.

The findings are rich. Invention yields substantial rents for white- and blue-collar workers. Education raises the returns to invention for both groups. Biological age appears to reduce returns, yet this negative effect is entirely due to older workers being farther from the human capital frontier, measured by time elapsed since their last degree. Control for that distance and the age penalty disappears. The calendar is innocent; the diploma's date is the culprit.

Employment tells the same story. The direct effect of invention is to lower the probability of non-employment, and this protective effect declines with time since education. Workers with more recent formal training benefit more. Fields differ: non-STEM educated workers receive a higher base return, STEM-educated seniors earn an extra return while non-STEM seniors do not, and the effect of distance to the frontier is, if anything, larger for non-STEM workers.

The interpretation reframes a social problem as a solvable one. Older workers' losses from invention trace to the depreciation of their human capital relative to the frontier. That diagnosis points to a remedy: retraining programs could help make creative destruction and economic growth more inclusive. Distance can be shortened; age cannot.

The parallel with today's technology is close. Artificial intelligence raises the stakes. AI is a wave of invention reshaping workplaces, and concerns about its effects on older workers are widespread. The critical variable, on this evidence, is the recency of skills. Workers whose education sits close to the frontier share in innovation rents; those whose skills have depreciated face greater risk. AI may accelerate human capital depreciation, making distance to the frontier even more important. A degree's shelf life may be shrinking.

The policy implication is constructive. Lifelong learning and retraining can reduce the distance to the human capital frontier, letting workers of all ages benefit from innovation. Programs updating skills periodically, in step with technological change, could help older workers capture invention rents and stay employed. In an AI-driven economy, such programs may be among the most effective tools for inclusive growth. A periodic refresh of skills could become as routine as a software update.

Blue-collar rents widen the circle. Innovation benefits extend beyond inventors and highly educated staff. Keeping workers across the occupational spectrum current broadens the sharing of gains. The factory floor collects part of the patent's value.

The STEM results add nuance. The link between field of education and returns to invention is complex, and distance to the frontier matters for both groups. Retraining should cover workers in all fields, recognizing that the frontier moves in many domains as AI spreads through the economy.

The data lesson matters too. Linking income, firm and patent data lets researchers trace invention's effects through firms to individual workers. Such infrastructure is invaluable for understanding the distributional effects of technological change, and similar efforts will be needed to track AI.

Stepping back, innovation's effects on workers depend on how current their skills are. What matters is distance to the human capital frontier. As AI transforms work, keeping skills close to the frontier will determine who shares in the gains, and this study supplies rigorous evidence for retraining as a pillar of inclusive growth.

Something for employers and policymakers to sit with: the question that matters is how long since the last real training. On this evidence, that number explains the age penalty, and it is one a firm can actually change.