Concentration of credit risk Assets that potentially subject us to significant concentration of credit risk primarily consist of cash and cash equivalents, restricted cash, short-term investments, accounts receivable and contract assets. We expect that there is no significant credit risk associated with cash and cash equivalents, restricted cash and short-term investments, which were held by reputable financial institutions in the jurisdictions where we, our subsidiaries and VIEs are located. We believe that it is not exposed to unusual risks as these financial institutions have high credit quality. 163 Table of Contents Accounts receivable and contract assets are typically unsecured and are derived from revenues earned from reputable customers. As of December 31, 2023, we had two customers, with accounts receivable balances exceeding 10% of the total accounts receivable balances. As of December 31, 2024, we had one customer, with accounts receivable balances exceeding 10% of the total accounts receivable balances. As of December 31, 2025, we had no customers, with accounts receivable balances exceeding 10% of the total accounts receivable balances. As of December 31, 2023, we had two customers, with contract assets balances exceeding 10% of the total contract assets balances. As of December 31, 2024, we had one customer, with contract assets balances exceeding 10% of the total contract assets balances. As of December 31, 2025, we had two customers, with contract assets balances exceeding 10% of the total contract assets balances. The risks with respect to accounts receivable and contract assets are mitigated by credit evaluations we perform on our customers and its ongoing monitoring process of outstanding balances. Business, customer, political, social and economic risks We participate in a dynamic and competitive high technology industry and believe that changes in any of the following areas could have a material adverse effect on our future financial position, results of operations or cash flows: changes in the overall demand for services; competitive pressures due to existing competitors; new trends in new technologies and industry standards; control of telecommunications infrastructures by local regulators and industry standards; changes in certain strategic relationships or customer relationships; regulatory considerations; and risks associated with our ability to attract and retain employees necessary to support our growth. Our operations could be adversely affected by significant political, economic and social uncertainties in the PRC. Currency convertibility risk We transact a majority of our business in RMB, which is not freely convertible into foreign currencies. On January 1, 1994, the PRC government abolished the dual rate system and introduced a single rate of exchange as quoted daily by the PBOC. However, the unification of the exchange rates does not imply that the RMB may be readily convertible into United States dollars or other foreign currencies. All foreign exchange transactions continue to take place either through the PBOC or other banks authorized to buy and sell foreign currencies at the exchange rates quoted by the PBOC. Approval of foreign currency payments by the PBOC or other institutions requires submitting a payment application form together with suppliers’ invoices, shipping documents and signed contracts. Additionally, the value of the RMB is subject to changes in central government policies and international economic and political developments affecting supply and demand in the PRC foreign exchange trading system market. Foreign currency exchange rate risk From July 21, 2005, the RMB is permitted to fluctuate within a narrow and managed band against a basket of certain foreign currencies. For the RMB against the U.S. dollar, there were depreciation of approximately 2.9% and 2.8% during the year ended December 31, 2023 and 2024, respectively. However, there were appreciation of approximately 4.2% during the year ended December 31, 2025.. It is difficult to predict how market forces or PRC or U.S. government policy may impact the exchange rate between the RMB and the U.S. dollar in the future. ​