Germany's Mitbestimmungsgesetz — What Fifty Years of Board-Level Codetermination Actually Delivered

The Mitbestimmungsgesetz (Codetermination Act) of 1976 requires German stock corporations and large GmbHs to give employees near-parity representation on the supervisory board (Aufsichtsrat): one-third of seats for firms with 500–2,000 employees, and up to half for firms above 2,000 employees (with the shareholder-elected chair holding a tiebreaking vote). It builds on an older tradition of works councils (Betriebsräte) dating to 1920, extended to the coal and steel sectors from 1951.
Because firms do not strategically shrink below the 2,000-employee threshold to dodge parity codetermination, economists have used it as a natural experiment (regression discontinuity design). Gorton and Schmid's widely cited 2004 study found that full parity board representation was associated with a market-to-book ratio roughly 31% lower than one-third representation, suggesting tension with shareholder wealth maximisation. More recent work by Jäger, Noy and Schoefer (NBER Working Paper 28921) reaches a more measured verdict: across a range of firm and worker outcomes — wages, employment, investment, outsourcing — the evidence points to "zero or small positive effects," with room for modest gains in productivity, wages and job stability as councils mature, but no significant shift in overall turnover.
Codetermination is a striking case where a popular, widely emulated governance model does not show the dramatic productivity or investment gains sometimes claimed for it in policy debates (for example UK and US proposals to import German-style worker board seats). What decades of firm-level data instead show is a durable institution that reliably keeps management and labour talking inside the boardroom, with a real but modest economic footprint — a useful corrective for any economic-development agency weighing worker-voice mandates as a growth lever.

Read the full analysis: https://www.bruegel.org/blog-post/codetermination-germany-role-model-uk-and-us