For those that are not familiar with the space, campaigns typically use voter contact software to record the results of the conversations they have with potential voters on the phones, at the doors, and over the Internet. In this case, the voter contact software that both the Hillary and Sanders campaigns were using, NGP VAN, had a bug which allowed both campaigns to access each other&#x27;s private, proprietary data (in this case, I believe, modeling data).<p>The Data Director on the Sanders campaign discovered the error and (he claims) was verifying and documenting the bug, which was then reported to the Democratic National Committee (DNC) and NGP VAN. The DNC claims these actions were not in good faith, and as a reaction cut the Sanders campaign off from the system.<p>This is a BIG deal for a campaign, so close to the first elections. Campaigns rely on that data to inform nearly everything they do, and rely on access to such tools to conduct their voter outreach program. Being cut off from the system is crippling for a campaign, likely why the Sanders campaign so quickly sued to get its access reinstated [1].<p>[1] - <a href="http:&#x2F;&#x2F;www.politico.com&#x2F;story&#x2F;2015&#x2F;12&#x2F;sanders-campaign-threatens-to-sue-dnc-216942" rel="nofollow">http:&#x2F;&#x2F;www.politico.com&#x2F;story&#x2F;2015&#x2F;12&#x2F;sanders-campaign-threa...</a><p>edit: typos