investing in Theranos. In the Tesla case, the SEC required CEO Elon Musk to resign as chairman and take several other compliance actions, including hiring independent directors to oversee the CEO's public statements about the company, after Musk tweeted that he was thinking about taking Tesla private.

• Serious push to protect retail investors: More than half of the agency's stand-alone actions this year involved wrongdoing against individual investors in cases that centered on fees and expenses and conflicts of interest for managed accounts; market manipulations; and fraud in unregistered offerings. Several actions centered on Ponzi schemes that tricked investors out of millions of dollars, according to the SEC.

• Cybercrime is a growing concern: The SEC formed a Cyber Unit late last year as part of an effort to crack down on cyberattacks. This year, the agency had more than 225 active investigations. In one case, the SEC alleged that false regulatory filings were used to manipulate the price of Fitbit stock. Another enforcement action targeted a day trader in Philadelphia accused of raking in at least $700,000 through a scheme that involved accessing the brokerage accounts of more than 100 victims to make unauthorized trades to inflate the stock prices of various companies.

• Doing more with less: The SEC has been dealing with a hiring freeze that began in 2016. Since then the number of employees and contractors at the agency has dropped by about 10 percent. But the agency's enforcement activity increased this year, when it filed 821 actions, compared with 754 last year.

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