The Brit was one of 19 people arrested in a huge police operation involving 1,400 officers to evict the squat in the 2nd district but he was the only one to be charged.
The charges for obstructing a police operation and damaging property were brought against the man last August, more than a year after the eviction took place.
“The proceedings were aborted, however, because the whereabouts of the man is not known, he has no fixed abode and his place of birth is also not known,” a spokesperson for Vienna provincial court Christina Salzborn told the ORF.
The eviction of the self-described anarchist squat – called Pizzeria Anarchia – took over ten hours, with many police dressed in riot gear and equipped with an armoured car and water hoses.
They were met with resistance from residents of the squat who had set up barricades including a booby trap, positioning a stove so it would fall on the police.
The house had been occupied by the activists for over two years. The owners of the building actually invited them to move into an empty apartment, in November 2011, for six months.
The place was badly in need of renovations and the owners hoped that the anarchists would scare off the older tenants who were refusing to move, and clear the way for a new real estate project.
However, the squatters became sympathetic to the tenants' plight, and decided to stay – so the owners requested they be evicted.
The police managed to evict the squatters following the hours long operation, arresting 19 of them, including seven from Austrian, seven from Germany and three from Romania.
The eviction, which the Interior Ministry said cost €870,000, was criticised by some Austrians who argued it was too heavy-handed.