BlackBerry has announced plans to lay off 4,500 employees, which represents 40% of its global staff and nearly $1 billion in net operating loss last quarter.

The company’s stock plunged 20% on the announcement, with shares trading at $8.36 per share in late-afternoon trading.

BlackBerry had been scheduled to release earnings next week. But the Canadian company said late Friday afternoon it expects a loss of about $950 million to $995 million for the quarter, including a massive inventory charge due to increasing market competition.

The BlackBerry, pioneered in 1999, was the dominant smartphone for on-the-go business people and other customers before Apple debuted the iPhone in 2007. Since then, BlackBerry Ltd. has been hammered by competition from the iPhone as well as Android-based rivals like Samsung.

BlackBerry has hired PricewaterhouseCoopers LLP to evaluate the company for potential buyers, according to Bloomberg.

Coincidentally, Apple released its new iPhone 5S and iPhone 5C on Friday.