In Oslo, where the world¡¯s biggest sovereign wealth fund decides how to allocate $1.4 trillion, a huge contradiction lurks.

The fund is trying to reconcile a sustainable-investing mantra with the billions it owns in companies that source cocoa from regions where children pick beans that feed the world¡¯s craving for chocolate. So far, it has chosen to stay involved rather than sell so it can push for positive change.

¡°We expect companies to work against child labor, but at the same time we recognize that child labor in supply chains and agriculture has complex underlying causes,¡± said Line Aaltvedt, a spokeswoman for the fund.