Telefónica, S.A.'s (BME:TEF) shares soared on December 20, 2023 morning after the Spanish government said on December 19, 2023 it would buy a stake of up to 10% in the company in a counter balance to a similar acquisition by Saudi Arabia's STC. Telefonica shares were up 6% at ?3.78 in early morning trading, on track to its best day since Nov. 22, 2021.

The share is the top gainer in the STOXX 600 index. State holding company SEPI (Sociedad Estatal de Participaciones Industriales) said on December 19, 2023 it would buy the shares in a way that would minimise the impact on market price though it did not give a time frame. A 10% stake had a market value of around ?2 billion ($2.19 billion) as of December 19, 2023 evening.

The move is a response to the STC announcement it had built a 9.9% stake in Telefonica in September.