Shares of BlackBerry Ltd. (BBRY) plunged nearly 16 percent to $10.69 in extended-hours trading Wednesday after the smartphone maker denied earlier reports of a possible takeover by Samsung Electronics Co. Ltd., reversing gains of as much as 30 percent earlier in the regular U.S. trading session. John Chen took over as chief executive officer of BlackBerry in November 2013 with the task of trying to turn around the company after it has struggled to compete with tech rivals, such as Apple Inc., Samsung and other Android smartphone suppliers.

Last month, BlackBerry disappointed investors by turning in quarterly earnings and revenue that missed Wall Street expectations. BlackBerry posted a fiscal third-quarter net loss of $148 million, or a loss of 28 cents per share, compared with a loss of $4.4 million, or $8.37 per share, a year earlier. Revenue in the previous quarter was $793 million, compared with $1.19 billion during the same period in 2013.

BlackBerry has struggled to gain traction in the consumer market, but it has a strong presence on the enterprise software side for governments around the globe. “BlackBerry has tried to form a little bit of a niche in security,” Adam Sarhan, founder and chief executive officer of Sarhan Capital, told IBTimes after the company unveiled its Passport smartphone at simultaneous global events in London, Toronto and Dubai on Sept. 24.

The smartphone maker already has a history of working with Samsung, which makes some analysts skeptical of the denial. BlackBerry and Samsung announced plans for a partnership in November 2013 to provide “end-to-end security” for Samsung Galaxy smartphones and tablets that are embedded with Samsung KNOX, hardware and software integrated security for Samsung mobile devices.

Keith Bliss, senior vice president at Cuttone & Co., agrees. “They’re still the pre-eminent player when it comes to data security across those networks. That’s really what’s kept them in survival mode right now,” Bliss told IBTimes in September.

BlackBerry’s stock price jumped nearly 30 percent Wednesday during the U.S. trading session following a report that South Korea's Samsung had approached it about a potential takeover for as much as $7.5 billion, according to an exclusive report from Reuters. Executives from BlackBerry and Samsung met last week to discuss a potential transaction, sources familiar with the matter told the wire service.

“BlackBerry has not engaged in discussions with Samsung with respect to any possible offer to purchase BlackBerry. BlackBerry’s policy is not to comment on rumors or speculation, and accordingly it does not intend to comment further,” the Canadian-based company said in a statement Wednesday.

Tech giant Samsung offered an initial price range of $13.35 to $15.49 per share, which is a premium of 38 percent to 60 percent over BlackBerry's current trading price, sources told Reuters.