Inner Mongolia Baotou Steel Union (SHA:600010) said a subsidiary paid back taxes of about 324.4 million yuan, according to a Tuesday filing with the Shanghai bourse.
The subsidiary's back taxes include payments for VAT, additional taxes, water conservancy construction, and late payment penalties.
The tax payment will impact the steel mill's 2026 profit by 233.5 million yuan.
Shares rose 2% during the midday break on Tuesday.