In the U.S., the company purchases about two billions eggs annually. Comparatively, since 2011, they've bought over 13 million cage-free eggs annually, so it's a pretty big move to secure enough supply.
The news follows recent changes by the fast food chain meant to improve food quality, including a commitment to source only chicken raised without antibiotics important to human medicine by 2017, slightly bigger Quarter Pounder beef patties, and butter instead of margarine on their English muffins and biscuits.