RIM stock ended the day down 56 cents, or 3.44 per cent, to $15.71 on the Toronto Stock Exchange, following a 7.6 per cent slide Monday.
As of Friday, RIM stock (TSX:RIM) had soared 50 per cent during January.
"The returns have been huge here, and for sure you're probably seeing some profit taking, some buy on rumour, sell on news," said Gareth Watson, vice-president of investment management and research at Richardson GMP Ltd.
"But also, the reality that the device is about to be launched... we don't know how successful it will be."
The smartphone pioneer once dominated the marketplace with its devices, which were affectionately dubbed "CrackBerrys" by devoted users.
But RIM has seen its marketshare eroded significantly by Apple's iPhone and Android-powered phones.
The unveiling of the new BB10 phones and operating system on Wednesday will mark the start of an advertising blitz that will stretch to social media, the Super Bowl and beyond, as RIM tries to regain its footing.
The smartphones are widely seen as a make-or-break product for the Waterloo, Ont., company.