Beyond that, the campaign is "proprietary".
defended the suspension on Friday, arguing that it was in line with the agreement the campaigns had with the committee not to access another campaign's proprietary information.
"We did not seek, nor do we have, nor did we receive, nor do we want any proprietary information from the Cahill campaign," he told reporters outside a campaign stop.
Aristotle uses publicly available voter-registration records (the company says it has nearly all the country's 145m registered voters on file), and a proprietary computer model to help campaigns target web ads at people who are likely to vote for a particular party.
The databases are expensive, the algorithms are proprietary, the results of experiments by campaigns are secret, and the analytics require special expertise.
But from the beginning it was colored with tension from the controversy over the Sanders campaign's unauthorized access to proprietary Clinton files on a joint voter database maintained by the Democratic National Committee.
The rule is named for Paul A. Volcker, a former chairman of the Federal Reserve who campaigned for the ban on proprietary trading.
On Wednesday, a breach in the firewall between the Democratic candidates' respective voter files, which are rented to the campaigns by the DNC, allowed Sanders campaign staffers to access Clinton's proprietary voter data.
Reachli's proprietary technology involves a relevancy algorithm to match campaigns with images on these sites, and then place an ad on it.
Leitch's campaign runs on Track & Field, Kouvalis' proprietary voter-tracking program.
