According to a report from All Things Digital, Apple’s vice president of worldwide marketing communications Allison Johnson is leaving the company to set up her own marketing and public relations firm. Johnson has held the VP position since 2005 and will officially leaving within the next few months.

There’s no dearth of marketing and communications talent at Apple, but Johnson’s exit from the company is still notable.

She’s a seasoned and respected executive who came to Apple from Hewlett-Packard, where she managed public relations during the brutal proxy battle over HP’s acquisition of Compaq Computer. A former co-worker there once described her as “prime minister” of HP.

At Apple, Johnson has managed global advertising for some of the company’s most revolutionary products and the iconic ads for them. Those ads have been created by TBWAChiatDay, which plays a powerful role at Apple.

No bad blood is brewing between Apple and Johnson as a result of her departure, sources said. The marketing whiz worked for the company since 2005, coming from Hewlett-Packard. Sources claim she’s leaving to start a new PR agency with Brandee Barker, a former Facebook PR person:

Sources said Johnson will begin work at the venture after negotiating her departure from Apple, which is likely to come sometime before the summer. Beyond that, the details are slim. The new firm doesn’t yet have a name or a client list, although presumably answers site Quora and social buying service Groupon, two of Barker’s current clients, would sign on with the venture.

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