Just a few months ago a case was started in Sweden based on such situation. The movie studio got hit by breach of contract by the publisher along with charges of illegal advertisement.

> Which specific laws are banning this practice in Sweden for private entities?

Marknadsföringslagen (2008:486) is the primary source for laws that regulate advertisement for private entities, however there is actually more. The European Advertising Standards Alliance has a local representation called Reklamombudsmannen, which is a self-regulating entity for advertisement. This one has some support by law, and some support by other means such as black-lists, and can issue fines. Last there is also the International Chamber of Commerce. Publishers in any form of media can also loose the right to publish, which is an automatic granted right which the court can take away. Since TV and radio is attached to spectrum allocation, there is also additional conditions on them in regard to advertisement (which is the reason why the movie studio got hit by a breach of contract in the above case).