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Oct 1 (Reuters) - Activist investor Starboard Value LP said it offered to acquire the remaining shares in RealD Inc after raising its stake in the 3D technology licensor.
Starboard offered $12 per share, a premium of 29 percent to RealD stock's Wednesday close and valuing the company at about $540 million.
RealD's shares were up 21 percent in extended trading.
"The time frames and capital requirements needed to support many of the company's growth initiatives appear to be well beyond what the public markets will bear", Starboard said in a letter on Wednesday to RealD's board. (1.usa.gov/1rMY8tq)
Starboard, which is the third-largest shareholder in the company, also disclosed that it had raised its stake to 9.9 percent from 9.1 percent.
Starboard recently said it had acquired a "significant" stake in Yahoo Inc and urged the Internet company to explore a merger with AOL Inc.
The activist investor is also pursuing a high visibility proxy battle with Olive Garden owner Darden Restaurants Inc .
Up to Wednesday's close, RealD's stock had gained about 9 percent this year. (Reporting by Anya George Tharakan in Bangalore; Editing by Sriraj Kalluvila)