UPDATE, 2:52 PM: BlackBerry shares have retreated 10.8% in post-market trading after it seemed to deny a Reuters story that said it has engaged in serious talks with Samsung about a possible deal. The mobile communications company says in a statement now that it “has not engaged in discussions with Samsung with respect to any possible offer to purchase BlackBerry.” Reuters says its report was based on “a person familiar with the matter and documents seen by Reuters.” BlackBerry declined to comment before the story ran, it added. BlackBerry says it has a policy “not to comment on rumors or speculation” and — having just done so — “does not intend to comment further.” In other words, shareholders are on their own.

PREVIOUS, 1:37 PM: BlackBerry shares shot up nearly 30% to $12.60 just before the market closed after Reuters reported that Samsung offered as much as $7.5 billion, mostly to pick up its portfolio of patents. The South Korean electronics giant proposed a price of between $13.35 and $15.49 a share, representing a premium of as much as 60% vs the trading price before news of the offer leaked, the news service says. It adds that BlackBerry and Samsung execs have enlisted advisers and met last week to go over details.

BlackBerry, whose products used to be de rigueur for executives and much of Hollywood, has been against the ropes since early 2011. Built around secure email communications, it failed to keep up with the Internet-focused innovations that Apple included in its iPhones and Google built into its Android operating system. BlackBerry accounted for just 2.3% of the U.S. smartphone market in mid-2014 vs 52% for Android and 42% for Apple.

Samsung has had more success in hardware sales, where it accounted for about 28% of U.S. smartphone sales in mid-2014 vs Apple’s 41%. But it wants to become less dependent on Android. Last year it had to delay plans to introduce a line of phones based on its Tizen operating system.