SHANGHAI, Nov 4 (Reuters) - Shanghai Shimao Co said on Thursday the Chinese developer will limit investor participation in seven Shanghai-traded bonds to help shield retail investors from volatility. Starting Friday, only institutional investors will be allowed to buy the bonds, while existing individual investors can choose to sell them, or hold until maturity, it said a filing to the Shanghai Stock Exchange. The company sees no major events that seriously harm its repayment ability, it said. (Reporting by Samuel Shen; Editing by Toby Chopra)