Before revision: U.S. sources have pointed the finger of suspicion at Huawei hardware since at least 2012, suggesting the possibility of the presence of backdoors in Huawei products , without ever providing any evidence to back this claim .
After revision: U.S. sources have pointed the finger of suspicion at Huawei hardware since at least 2012, suggesting the possibility of the presence of backdoors in Huawei products .