Company names are written in brackets on the signboards of subway stations, as a result of naming rights contracts between Seoul Metro, the subway operator, and the companies. (Seoul Metro)

Seoul Metro, the public corporation that operates the subway system in Seoul, is putting the names of 30 subway stations up for sale.

The upcoming auction will involve 18 subway stations, the naming contracts of which have expired, along with 12 additional stations in downtown and commercial hub areas. They include Gangnam Station on Line 2, one of the busiest stations, as well as Seongsu and Sinsa Stations, in hip Seongsu-dong and Sinsa-dong, respectively.

The new names will be displayed in brackets alongside their original ones at subway entrances, on platforms and on metro maps. In-train and in-station announcements will also use both names.

Companies and institutions located within 500 meters of the stations are eligible to bid for naming rights. Naming contracts will be valid for three years and contracts can be extended once.

Seoul Metro will receive applications from potential bidders by June 21.

The subway operator has auctioned off the rights to the names of subway stations since 2016 to make up for deficits in its subway operations.

It recorded a net loss of 964.4 billion won ($738 million) last year, up 64 percent from 586.5 billion won in 2019, largely due to free rides offered to senior citizens and the decrease in the number of passengers due to the pandemic.

As of this year, 38 companies and organizations added their institutional names to the signage of 42 stations. Euljiro 1-ga, for instance, has been paired with the Industrial Bank of Korea and Euljiro 4-ga with BC Card, while Apgujeong on Line No. 3 and Yeoksam on Line No. 2 featured the names of Hyundai Department Store and Centerfield, respectively,

Seoul Metro has earned 16.9 billion won from the sale of naming rights so far, officials said.