Securities companies generally do not bear losses for investors in bond funds. Fund companies are responsible for the operation of bond funds, while securities companies are only responsible for providing bond trading services. If there is a thunderstorm in the bond fund, the fund company will deal with it according to the fund contract and legal provisions, and may take different measures, such as accountability and fund liquidation. Investors can bear corresponding losses according to the risk tolerance and loss sharing rules of the Fund. Therefore, if a bond fund explodes, investors usually have to bear the losses themselves, and securities companies will not directly help investors repay. However, the specific situation needs to be determined according to relevant laws and regulations and contract terms.