Since dark money changed politics as we know it in the post-Citizens United era, the top 15 dark money groups have spent more than $600 million in secret money in our elections.

These groups accounted for more than 75 percent of the $800-plus million spent by all dark money organizations between January 2010 and December 2016. They spent the majority of this money on negative attack ads, criticizing candidates from the shadows while purposefully hiding their donors and masquerading as trade associations or “social welfare” nonprofits.

Dark Money Illuminated” profiles the top 15 dark money groups and shines light on approximately 400 donors and donor organizations who have funded these groups, including companies, trade associations and labor unions. Issue One created a searchable, first-of-its-kind database containing nearly 1,200 transactions linked to these donors, each supported by primary source documents.

Watch our training with the Center for Responsive Politics and the Campaign Legal Center on how to track dark money in politics and what can be done to curb it: