The two women, from the group Femen, demonstrated in the Svea Courts of Appeal building Tuesday morning, The Local.se reported.
The women's chests were painted with the slogan, "Stop legalizing rape," and their backs read, "No means no."
After a few minutes of protest, security forces escorted the women out of the building.
The incident occurred in March, when five teenage boys allegedly sexually assaulted a 15-year-old girl at a party. A sixth boy was distributing condoms.
The boys were initially convicted of aggravated rape, but their charges were cleared last week.
The appeals court ruled that per a rewritten sex crimes law, the victim was not helpless because she was not in an incapacitated state.
Prosecutors argued the girl's fear led her to be helpless, but the court based its ruling on the fact that she was not unconscious, excessively drunk or physically hurt.
Prosecutors said they may take the case to Sweden's Supreme Court.
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