When Elon Musk disclosed his stake in Twitter Inc., he had a choice.
Shareholders who intend to remain “passive” -- those who don’t seek to influence or change control of a company -- file a shorter form with the U.S. Securities and Exchange Commission, called a 13G. Those angling for board seats or seismic shakeups typically file a longer and more in-depth form, a 13D, within 10 days of buying their stake. The rule applies to anyone acquiring 5% or more of a public company’s stock.
