A revised antimonopoly law featuring lenient punishment for those who come clean about their illegal business activities, including collusive bidding and cartels, took effect Wednesday.

The law, revised for the first time since 1977, exempts first declarers of illegal business activities from paying charges and protects senior officials from criminal accusation.

Accused companies, however, face higher fines under the revision.

The government is hoping the carrot and stick approach will discourage companies from relying on bidding and cartels and curb such illegal business activities.