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DIVESTITURE OF STEM CELL ASSETS (Details) (USD $) |  |  |  | 0 Months Ended
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May 28, 2014 | Jun. 30, 2014 Series A common stock | Oct. 01, 2013 Series A common stock | May 28, 2014 Asterias contributions Series A common stock | Oct. 01, 2013 Contribution Agreement Asterias contributions Geron
DIVESTITURE OF STEM CELL ASSETS |  |  |  |  |
Shares issued |  |  |  |  | 6,537,779
Percentage ownership in Asterias |  |  |  |  | 21.40%
Number of shares of entity's common stock outstanding | 156,924,100 |  |  |  |
Common stock distribution ratio |  |  |  | 0.0417 |
Carrying value of common stock |  | $ 0 | $ 0 |  |
Liability relating to contractual obligation to distribute common stock |  | $ 0 |  |  |

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