The operators of a spamming business also stole customer records containing private data from two companies.
The lawsuit is the latest fallout from a financial scandal that has caused Toshiba's stock price to fall 40% since May.
Grant Thornton reached a $4.5 million settlement with the SEC in which the audit firm admitted wrongdoing.
The perpetrators 'cloaked their scheme in technological sophistication and jargon, but the fraud was simple at its core,' said an SEC official.
The suit followed the U.K. grocer's admission that it overstated half-year profits by $377 million because of accounting errors.
The employee's position in the firm's compliance department allegedly gave him access to confidential information in investment bankers' emails.
The fraud involved real estate tax lien certificates that the broker told clients would earn 6% to 9% annually.
The Swiss drug maker allegedly turned specialty pharmacies into a "biased sales force" for its medications.
The SEC alleges stock promoter Shane Whittle orchestrated a "pump-and-dump" scheme that artificially inflated the coffee distributor's share price.
Not only that, they're more likely to be promoted to the top job permanently if they do.