article: The country's Football Association (CFA) is proposing the measure for loss-making clubs in order to try to curb the league's extravagant spending. Chinese clubs spent £331m during the country's winter transfer window, which was more than their English Premier League counterparts in January. The proceeds from the tax would go into a government-run fund. If enforced, the measure would in effect double the fee for any player. Manchester United striker Wayne Rooney and Chelsea striker Diego Costa are among the high-profile players to be linked with the Chinese Super League (CSL), with the transfer window open until 14 July. Media playback is not supported on this device In the last transfer window, Shanghai SIPG bought Brazil international Oscar for £60m from Chelsea, while Shanghai Shenhua spent £40m on Carlos Tevez. The Argentina striker signed a deal worth a reported £310,000 a week. At the time, a spokesperson for China's General Administration of Sport said clubs in the country were "burning money". Limits on the number foreign players in squads were put in place for the current season, which runs from March to November. Only three non-Chinese players can now be fielded in a fixture in a move the CFA hoped would tackle "irrational" spending. Costa was a target for Tianjin Quanjian but the club's owner, Shu Yuhui, said in January that a bid to sign the forward had been scuppered by new CSL rules limiting the number of foreign players. In each game next year, clubs will also have to field as many Chinese under-23 players as overseas players. BBC Sport's Simon Stone: The Chinese Super League transfer window has raised the potential for another massive deal being done for Wayne Rooney. A move to China is one of a number of options for Rooney, which also include remaining at United for the final year of his contract. However, he may wish to consider the fate of former team-mate Carlos Tevez, who joined Shanghai Shenhua on a mega deal earlier in the year. Neither the team nor Tevez are performing to expectations and when the Argentina international was spotted at a theme park after missing a game through injury this weekend, fans went on social media to condemn him, with one saying he has "the worst attitude in the team's history". Big money. Big demands.
summary: Chinese Super League clubs face a 100% tax on signings as their mid-season transfer window opens on Monday.