Hans Fredrik Neij, Gottfrid Svartholm Warg, Peter Kolmisoppi and Carl Lundström, are suspected of organising and running The Pirate Bay, and thus "promoting other people's infringements of copyright laws," according to charges filed by senior public prosecutor Håkan Roswall.
According to the prosecutor, their work with the site has meant that they "promoted other people's copyright breaches."
The charge sheet includes 33 cases of alleged copyright infringement, of which twenty involve music, nine are movie-related and four refer to computer games.
The prosecutor has called for the accused to pay damages of 1.2 million kronor ($185,000) to the Swedish state. He has also asked for the suspects' computers to be confiscated.
Evidence gathered by the prosecutor includes information provided by the suspects as well as interviews with staff at the International Federation of the Phonographic Industry (IFPI) and Sweden's Anti-Piracy Agency (APB), a non-governmental organization representing the entertainment industry.
The prosecutor has also pointed to documents detailing data traffic and a series of e-mail messages.
Roswall further noted that The Pirate Bay had sold advertising on its site.
While Håkan Roswall did not wish to comment on the charges, IFPI's managing director Ludvig Werner said he was pleased with the way the case was progressing.
"It is very satisfying that the prosecutor shares our view that the The Pirate Bay's activities are illegal and has brought charges accordingly.
"Sweden has developed an unflattering reputation as a sanctuary for internet pirates. The trial is going to generate a lot of interest worldwide," said Werner in a statement.
Magnus Eriksson, a spokesman for pro-file sharing lobby group Piratbyrån, predicts that The Pirate Bay will survive the trial even in the event of a guilty verdict.
"The Pirate Bay is not going to be down for a single minute. The Pirate Bay is now established in a number of countries, so there's no one place in which to push the off button," he said.
Eriksson added that he would be surprised if the suspects were convicted of the alleged offences.
"It's not very likely. In the course of the investigation there have been attempts to bring up various things that The Pirate Bay has supposedly been guilty of. Before it was financial crime, and now this accessory thing seems to be the last straw for the prosecutor," he said.
Asked whether musicians and film-makers did not have a right to be paid for their work, Eriksson replied that file-sharing contributed to a greater general interest in music and film.
"Artists have a lot of ways to earn money, and in that respect they are actually helped by file-sharing.
"These charges will not help artists. Instead they are part of a wider campaign from the anti-piracy side to stop people downloading," said Eriksson.