At 9:04 a.m. Eastern Time on Oct. 22, 2013, representatives from Panera Bread, the chain of fast-casual restaurants, uploaded a news release about the company’s latest quarterly earnings to Marketwired’s service.

In the release, Panera Bread announced that it was revising its earning guidance downward for the fourth quarter of 2013. It had turned a profit that was in line with what analysts on Wall Street had been expecting, but fewer people were coming to its restaurants and labor and food costs were rising. It was not an altogether rosy picture the company was going to paint when its release became public that day after stock market trading closed at 4 p.m.

Weeks earlier, Arkadiy Dubovoy, the owner of a APD Developers, a company based in Alpharetta, Ga., began to prepare.

APD designed and built residential communities and condominiums, but Mr. Dubovoy also controlled brokerage accounts at Charles Schwab, E-Trade, Fidelity, Merrill Lynch and TD Ameritrade.

On Oct. 8, Mr. Dubovoy received an empty email from a relative who split his time between Georgia and Ukraine. Attached to the email was a so-called wish list — a picture of a spreadsheet that contained the information about 18 publicly traded companies and the schedule for their earnings releases. Panera was on the list.