The court said the three men had entered plea agreements and been sentenced to house arrest for espionage, racial discrimination and criminal association.
The trio were among 11 men arrested in September, also accused of defacing Jewish sites, in an alleged plot aimed at inciting hatred and being trained under the "instruction of a foreign intelligence service", according to the Interior Ministry.
Nine pig heads, considered impure in Islam, were found in early September, 2025 outside mosques in Paris and the surrounding region, sparking outrage and alarm over rising anti-Muslim hatred.
In late April, the Holocaust Memorial, three synagogues and a restaurant in Paris were defaced with green paint.
The case against the eight co-accused is ongoing, the court said in a statement to AFP.
The three men's sentences range between six and 18 months under home detention, while one of the men can still appeal his sentence.
Three Serbs have already been charged and jailed in France as well.
Previously, Serbian investigators said they were also seeking a foreign national for his role in training the group.
