Mexico's Grupo Aeroportuario Centro Norte (OMA) said on Friday that Banco Santander's Mexico unit had sold 0.9 percent of shares in the company, which caused the trading volume to exceed normal ranges on the Mexican stock exchange.
OMA said Santander sold 3.7 million "series B" shares, which were part of an equity swap with Aeroinvest, a subsidiary of ICA, Mexico's largest construction company which is in default on debt payments.
Santander last week sold 27.8 million shares of OMA as part of the same equity swap on behalf of Aeroinvest.
