The global cage-free egg transition is the largest farm animal welfare reform in history by number of animals affected. Over 1 billion laying hens (of ~8 billion globally) are now in cage-free systems. Progress has been uneven across regions, with significant welfare implications for both transition speed and implementation quality.
Battery cages confine hens in 550 cm² — less than an A4 sheet — preventing: wing extension, turning around, normal postural changes, nesting behavior, dustbathing, perching, and most social behavior. The scientific consensus on battery cage welfare is unusually clear: the behavioral deprivation is severe and the welfare state of hens in battery cages is poor. Cage-free systems, whatever their own challenges, address these fundamental behavioral deprivations.
EU leadership: Battery cages banned since 2012; enriched cages now being phased out following End the Cage Age initiative. UK ahead of EU: 60%+ free-range and cage-free. Switzerland banned all cages including enriched. US: California Prop 12 (cage-free mandate in force from 2023) is the most significant US development, affecting the world's fifth-largest egg market and driving significant transition. Asia is the critical remaining frontier — China alone keeps 4-5 billion hens, almost entirely in battery cages.
The World Animal Protection corporate tracker monitors 400+ company commitments. As of 2025: ~60% of committed companies have made "good progress" (50%+ of supply cage-free); ~25% "some progress"; ~15% "insufficient progress." Deadline pressure from 2025 commitments has created significant market shift. Companies with formal third-party verification show higher compliance rates than self-reported only.