The role of regulation here is to make sure that apropriate controls and disclosure is in place to make sure that those prospective new shareholders have the in

The role of regulation here is to make sure that apropriate controls and disclosure is in place to make sure that those prospective new shareholders have the information they need to apropriately value what they are buying. The regulators already ensure this in various ways: a) It's illegal for Qualcomm to transmit any information to the activists before it's transmitted to the global markets. For instance, back in April, Qualcomm publicly responded to Jana: http://blogs.wsj.com/digits/2015/04/13/qualcomm-responds-to-activist-investor/ http://blogs.wsj.com/digits/2015/04/13/qualcomm-responds-to-... It would be insider trading if Jana were told anything that was not told to everyone. b) Folks who own significant shares of a public company (I think 5%), i.e. activists, are obligated to disclose it. c) Activists generally publish their activism. For example, here is a higher up at Jana talking to CNBC about Qualcomm: http://www.cnbc.com/2015/04/13/qualcomm-should-consider-breakup-jana-partners-founder.html http://www.cnbc.com/2015/04/13/qualcomm-should-consider-brea... The reason they do this is in order to encourage other shareholders to vote the same way they do. No one is being ripped off. Share values are being driven up because the market believes Qualcomm's prospects for long term cash are lower than the prospects for short term cash. If you disagree with this claim, feel free to get rich with a short position.