(Reuters) -BHP Group shares fell 4% on Friday a day after revealing a $38.8 billion bid for Anglo American as investors feared a deal could erode BHP's profitability especially if it has to sweeten its offer. The company's Australian stock did not trade on Thursday as the Australian share market was closed for a holiday. Questions about jurisdictional risks in South Africa and other regions, and concerns that Anglo American's businesses are lower margin than BHP's led to a share sell off, said RBC analyst Kaan Peker in Sydney.