In a reversal of trend of U.S. companies moving overseas to save on taxes, Walgreens said on Wednesday it would buy the stake in Alliance Boots it doesn’t already own, for $15.3 billion in cash and stock but keep its current Illinois tax address once it takes full ownership of the chain.

Walgreens is purchasing the remaining 55 percent stake in Europe’s largest pharmacy retailer from Alliance Boots GmbH in the second step of a two-step deal, having already purchased a 45 percent stake in the Swiss health and beauty retail chain in 2012 for $6.7 billion.