The anarchist Rouvikonas (Greek for Rubicon) group hit the wrong target on Sunday when members threw paint at a building in Maroussi, northern Athens, police said on Monday.
Instead of the offices of German digital giant Siemens, the perpetrators attacked the offices of three other firms. According to reports, the Siemens offices were moved to another location in the same building complex three years ago.
Police said group members hurled some 20 bottles of red and black paint at the building on Agisilaou Street early on Sunday. The incident was the latest in a string of attacks by the group in recent weeks.
On Thursday, members gathered outside the Athens home of New Democracy leader Kyriakos Mitsotakis. In July, group members broke through security to enter the courtyard of Parliament.