Why don't you sell shares to Amber Trade:
"We are ready to buy back all coins (shares in the company) bought from us at any time in any rounds of share offering at the purchase price. Thus, there is no risk of losing your investment (...) For anonymous investors the procedure of repurchases of shares is the following: they have to inform the company about their intention to withdraw from shareholdings by sending a note to the company’s e-mail address as well as sending the corresponding number of coins to the company’s wallet. After that the company will return the full amount of money to the specified address of a bitcoin wallet within the next 5 days."