In January 2007, a Los Angeles Times investigation by Charles Piller, 'Dark Cloud Over Good Works of Gates Foundation,' reported that the foundation's endowment was heavily invested in companies whose conduct ran counter to its charitable aims. Examples included holdings in oil companies linked to pollution in Nigeria's Niger Delta — near communities the foundation funded for health programs — as well as pharmaceutical firms that priced drugs out of reach and heavy polluters; the paper estimated roughly 41% of the portfolio was in such companies. The foundation initially said it would review its investment policies, but soon announced it would keep its approach of maximizing returns and managing investments separately from grant-making. The reporting sparked a lasting debate about 'mission-aligned' investing by large foundations.