Pasedena, California-based investment management firm Primecap Management Co. recently doubled its investment in BlackBerry vendor Research In Motion. According to a recent regulatory filing, Primecap now owns 26.4 million shares of RIM stock valued at about $577 million as of Monday’s close, and the stake represents approximately 5% of RIM’s total outstanding shares. According to Bloomberg, Primecap’s stake at the end of the second quarter of this year was approximately 2.5%. As numerous analysts continue to cut their price targets on RIM stock, Primecap’s continued investment could represent a vote of confidence in RIM’s new BlackBerry 7 phones and its future QNX phones as well, which are due to begin launching in the first quarter of 2012.