1. Report Industry Investment Rating No relevant content provided. 2. Core View of the Report The implementation of the new policy of resuming VAT on the interest income of newly issued bonds after August 8, 2025, will have a significant impact on the spot bond market and will also be transmitted to the pricing logic and trading strategies of Treasury bond futures. The key to whether there will be inter - period gaming opportunities or short - squeezing phenomena in Treasury bond futures lies in whether the CTD bond (cheapest to deliver bond) switches. The T contract may be a special case in the subsequent CTD bond changes, and there may be inter - period arbitrage opportunities and short - squeezing [1][6]. 3. Summary According to the Directory 3.1 Whether the Cancellation of Tax Exemption on Treasury Bonds Will Lead to CTD Bond Switching: The T Contract Is a Special Case - Generally, new bonds are difficult to replace old bonds as CTD bonds. New bonds with longer durations need to be fully discounted, which is difficult to achieve in practice. However, the 7 - year new bond in the T contract's deliverable bonds has a relatively short duration and only needs a small discount to become the CTD bond [11][12]. - There are two common empirical rules for identifying CTD bonds: when the spot bond yield is higher than the coupon rate (3%) of the Treasury bond futures virtual bond, high - duration bonds tend to be CTD bonds; when it is lower, low - duration bonds tend to be CTD bonds. For bonds with similar durations, the one with a higher yield to maturity is more likely to be the CTD bond [11]. - For TS, TF, and TL contracts, the newly issued bonds are generally of longer duration among the deliverable bonds, so they need to be significantly discounted to replace old bonds as CTD bonds. For the T contract, the 7 - year new bond only needs to have an issue rate about 3 - 6bp higher than the active bond to become the CTD bond for the 2512 or 2603 contracts, while the 10 - year new bond needs an issue rate about 30bp higher [14][17][18]. 3.2 How Will the Inter - period Change After the Cancellation of Tax Exemption: Focus on Contracts with CTD Bond Switching - The key to whether there are inter - period arbitrage opportunities after the cancellation of tax exemption on Treasury bonds lies in whether the CTD bonds of near - and far - month contracts switch. If the CTD bonds switch, considering the tax - exemption effect, the contract with the old bond as the CTD bond may be stronger than the one with the new bond, and inter - period arbitrage can be carried out [19]. - Contracts where CTD bonds are more likely to switch are TS2603, T2603, and T2512. With the new issuance of 2 - year and 7 - year Treasury bonds on September 12, there may be opportunities to focus on the inter - period spreads of TS2512 - TS2603 and T2512 - T2603 [7][20]. 3.3 Will There Be a "Short - Squeezing" in Treasury Bond Futures After the Cancellation of Tax Exemption on Treasury Bonds? - The possibility of short - squeezing in Treasury bond futures contracts with old bonds as CTD bonds is relatively small. The large stock of old bonds and subsequent issuances ensure sufficient supply, and excessive chasing will reduce their cost - effectiveness, thus suppressing the buying sentiment [23][25]. - Contracts where CTD bonds may switch to new bonds may face short - squeezing pressure. New bonds have low supply and circulation at the initial issuance stage, and the market lacks experience in dealing with new bonds as CTD bonds. The T contract and TS2603 contract are more likely to have CTD bond switches, and the T contract may face more severe short - squeezing pressure due to its large delivery volume and the relatively poor liquidity of the 7 - year Treasury bond [25].