CBS said that Last.fm will continue to operate as an independent entity, and that it plans to keep Last.fm's management team including its three co-founders.
Last.fm operates a social networking service for music. The software tracks the songs that users play and serves up recommendations based on properties such as similar genres and artists currently touring near the user's location.
Last.fm raised most of its money through venture capital investors, and expects CBS' deep pockets to let it speed up its rate of innovation.
"This deal gives us a chance to really make Last.fm shine, and gives us more flexibility than other funding options for doing all the crazy stuff we've had scribbled on whiteboards for years," co-founder Richard Jones wrote on a company blog.
CBS expects that Last.fm's user base will give the media giant further access to a younger, tech-savvy demographic.
"Last.fm has a great management team that understands how to build an engaged and passionate community where users learn, discover and share music globally," said CBS chief executive Leslie Moonves.
"Its demographics also play perfectly to CBS' goal of attracting younger viewers and listeners across our businesses."
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