The Antitrust Authority launched an investigation into the Steimatzky bookstore chain this weekend over suspicions that it violated antitrust law and merger terms.

The trustbuster also announced that it is investigating other entities in the sector, most likely a reference to Steimatzky's competitor Tsomet Books.

For years, the CEOs of both chains have said that their companies are having a hard time surviving due to the tough competition between the two.

Recently, the country's publishers took an unusual step and united to complain to the Antitrust Authority about the dynamics in the sector. The move came after Steimatzky's CEO told publishers that if they participated in Tsomet's sales, their books would not be marked down at Steimatzky.

Steimatzky had argued that it had the right to differentiate itself from other retailers.

Steimatzky receives more than 50% of the purchase price for every book sale, said one publisher.