On Sept. 4, employees of Good Technology, a mobile security start-up in Sunnyvale, Calif., awoke to discover that their company was being sold to BlackBerry, the mobile device and software maker.

Some workers immediately began trying to figure out what it meant for Good to abandon its long-anticipated plan to go public — a move that would have potentially turned their shares in the start-up into gold. They didn’t get firm answers that day, but the prospects did not look great.

Around 9 a.m., hundreds of employees filed into a conference room or started up videoconference software to watch Good’s chief executive, Christy Wyatt, discuss the sale. Ms. Wyatt introduced BlackBerry’s chief, John S. Chen, who winkingly apologized for how his deal makers had driven Good’s final sale price down to $425 million, less than half of the company’s $1.1 billion private valuation.

“They’re very polite when they’re beating you over the head,” Ms. Wyatt joked in response.

Just how punishing that price was became clear in late September. In an investor document about the sale that was distributed to shareholders, employees discovered their Good stock was valued at 44 cents a share, down from $4.32 a year earlier. In contrast, preferred stock owned by Good’s venture capitalists was worth almost seven times as much, more than $3 a share. The paperwork also showed that Good’s board had turned down an $825 million cash offer just six months earlier, in March.