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Charles and David have run fundraising/seminars on conservative public policy and political strategy twice a year since 2003. Only about 17 people participated in 2003, but that grew to around 500 in early 2016. The seminars grew from raising less than $100 million in 2008, under $300 million in 2014, and somewhere between $700 and $900 million for the 2016 election cycle.[38] The gatherings were characterized by great secrecy (participants were routinely urged to destroy all paperwork of the gatherings), commitment to conservative free market ideology, and the wealth of the participants, known as “investors” (in 2015, for example, 18 billionaires were present at a seminar). An example of a seminar at the network gatherings was one entitled “Understanding and Addressing Threats to American Free Enterprise and Prosperity”, at the June 2010 event in Aspen, Colorado. The meeting invitation stated that “[our] prosperity is under attack by the current [i.e. the Obama] Administration and many of our elected officials” and “we cannot rely on politicians to [defend our free society], so it is up to us to combat what is now the greatest assault on American freedom and prosperity in our lifetimes”.[96] The seminar program indicated that past meetings have featured speakers including Supreme Court Justices Antonin Scalia and Clarence Thomas; Governors Bobby Jindal and Haley Barbour; commentators John Stossel, Charles Krauthammer, Glenn Beck, and Rush Limbaugh; Senators Jim DeMint and Tom Coburn; and Representatives Paul Ryan, Mike Pence, and Tom Price.[97] Some presentations at the gatherings are restricted. Guests may be required to give up their cell phones, media presence limited to only “a handful” of organizations, and photos and videos “strictly prohibited”.[92]