FAT cats and big bonuses routinely stoke public anger. Now shareholders are pig-wrestling mad. On April 14th investors in BP rejected a pay rise for Bob Dudley, the oil firm’s boss, furious that he had got a 20% bump in his compensation last year (pension included) for overseeing the company’s biggest-ever operating loss. “Let me be clear,” soothed Carl-Henric Svanberg, BP’s chairman. “We hear you.”

BP’s shareholders are not the only ones being bolshie. On the same day, investors also slapped down Smith & Nephew, a FTSE 100 maker of medical devices, for waving through bonus payments even though targets set under its own pay policy had not been met. Fresh boardroom embarrassments loom. Shareholder-advisory firms have issued many more recommendations to vote against FTSE firms’ pay policies this year than last. Their targets this week included Anglo American, a mining firm, whose boss presided over a loss of £3.7 billion ($5.6 billion) in 2015 but took home a bonus of almost £1m. VW’s board is trying to head off trouble at the pass: it has said it will cut bonuses significantly, given the carmaker’s emissions scandal. Citigroup is lobbying its shareholders to ignore criticisms of its pay policies.

These belches of discontent are striking. First, public breaches between investors and directors happen rarely. True, the BP vote was a charade. It was an advisory vote, not a binding one; Mr Dudley had already banked his pay before shareholders rejected it. Nonetheless, any sort of dissent is unusual. It has been six years since the Dodd-Frank act gave shareholders in American firms an annual “say on pay” vote: the vast majority of them sail through. Less than 1% of S&P 500 firms suffered a defeat on pay last year; half got approval from more than 95% of their shareholders. Apart from a brief “shareholder spring” in 2012, it has been the same in Britain: just one FTSE 100 firm lost a pay vote last year.

Second, pay structures have shifted shareholders’ way in the past few years. The financial crisis underlined how managers could bank millions while shareholders picked up the pieces; public anger over inequality has made boards more conscious of the bad publicity that comes with egregious pay; and the votes on pay have given investors more leverage. Compensation committees claim to have forged a much tighter link between bosses’ pay and corporate performance. There is something to this. The percentage of S&P 500 firms tying pay to performance has jumped from 63% to 83% since 2011, according to Equilar, a research firm.

What, then, explains the current mini-mutiny? Investors have not had some sort of epiphany about the evils of excess pay for executives. The amounts of money involved in CEO pay may be enormous to the eyes of individuals, but they are trifling in corporate terms. Google’s chief executive, Sundar Pichai, just landed a pay award that could leave him $200m better off, for example. But if he makes decisions that add just 1% to the market capitalisation of Alphabet, Google’s parent company, that would be a $5 billion gain to shareholders. Pay is not as big a priority for shareholders when things are going well.

But when investors suffer—as those in oil and mining certainly have over the past year—and executives do not, the mood changes. Willis Towers Watson, another consultancy, analysed the recommendations that Institutional Shareholder Services, a shareholder-advisory firm, issued in America last year: 86% of those advising a “no” vote on pay reflected concern about disconnects between remuneration and performance.

Firms are supposedly making compensation more contingent on performance, yet these disconnects are still happening. One reason for this is complexity. Creating pay structures that perfectly reflect performance is a mug’s game. That hasn’t stopped an entire industry of consultants and proxy advisers from trying. Wading through the remuneration policies of listed firms deserves a bonus in itself: pages of dense text describing varieties of equity award with different triggers for vesting, some related to share prices, others to operational and financial measures.

It all looks very clever on paper. Indeed, BP’s shareholders voted en masse in 2014 in favour of the very pay policies that spat out Mr Dudley’s pay rise this year. But the results can be perverse. Setting detailed targets risks distorting behaviour. The pay policy at Valeant, an imploding drugs firm, used to be lauded for its emphasis on performance; plenty now reckon that setting a target of 15% annual growth in the share price helped it towards disaster. In March a government-sponsored review into gender diversity in British boardrooms called for bonuses to be linked to diversity targets. That would encourage gaming, says Alex Edmans, an academic at London Business School.

Comparing the performance of a firm to a group of industry peers also has an obvious logic to it. Otherwise executives can get rewarded or hurt by things outside their control: a stockmarket buoyed by easy central-bank money, or a slump in the oil price. But falling a bit less far than the worst of your peers, which was BP’s achievement in 2015, is an odd definition of success. It certainly isn’t one that aligns managers’ and investors’ interests.

Comp mentis

In the face of these sorts of anomalies, some heretical thoughts are surfacing. A Harvard Business Review article published earlier this year argued the case for getting rid of variable pay altogether and paying bosses a fixed salary. Shareholders will not go for that. But performance-based pay needs to be simpler: one option is to award stock without setting any performance-based conditions at all, but restricting executives’ ability to sell. That would both tie managers’ payouts to long-term performance, and reduce incentives to game results. This month’s outbreak of rebelliousness may look like a straight fight between tin-eared boards and wronged shareholders. Investors themselves have played their part in bringing about the outcomes they now oppose.