Research In Motion Ltd. will pay $1.2 billion to buy back 21 million of its common shares, the wireless device company said Thursday.

The purchase would represent roughly 3.6 per cent of the company's current float of shares. RIM hasn't bought back any of its own shares during the past year.

The plan will take effect starting Nov. 9.

"RIMs board of directors believes that a share repurchase program at this time is in the best interests of RIM and its shareholders," the company's board of directors says in a release. "[It] will not impact RIMs ability to execute its growth plans given the strength of RIMs balance sheet and expected cash flow generation over the next several quarters."