Gender quotas are used to address gender disparities, but they may trigger backlash that undermines their effectiveness. In an online hiring experiment, requiring recruiters to hire a female candidate for one position leads them to penalize women in other, uncovered positions, offering lower salaries and making them twice as likely to receive no offer. No such effect arises when quotas mandate hiring men. Backlash emerges among supporters and opponents of equity policies, and renders the quota policy ineffective. Under the quota, women are evaluated jointly with quota beneficiaries, unintentionally raising the bar for the group the policy aims to promote.