At 0810 GMT, shares of the UK telecom firm were trading 2.2% higher at 132.25 pence. BT declared the shareholding soon before the London stock market closed on Wednesday, and its shares rose 1.1% at the closing.
The Slim family’s interest in BT, which includes Control Empresarial de Capitales, Inbursa, and Dominum, is worth at 407.1 million pounds ($521 million), according to the company’s closing share price on Wednesday.
Slim’s investment makes him one of BT’s largest stockholders and the most recent high-profile industry person to do so. According to FactSet, the largest stakeholder in BT is Franco-Israeli telecommunications entrepreneur Patrick Drahi, who owns 24.47% of the company. Deutsche Telekom owns 12.02%.
“We welcome any investor who recognizes the long-term value of our business,” BT stated on Thursday. “We look forward to engaging with Inbursa, just as we do with all investors.”
The Slim-controlled firms did not immediately reply to calls for comment.
Slim created Mexican telecoms giant America Movil, which has made several investments in Europe over the years. America Movil controls 59.1% of Telekom Austria, according to the Austrian company’s website. According to FactSet, the Mexican company also owns 6.7% of Royal KPN, a Dutch telecom provider.