District and Sessions court Judge Surendra Singh Sisodiya held Khalid, Sami and Shahja guilty for possessing arms and distributing objectionable pamphlets in Shyamnagar area of Dhar in 2008 and imposed a fine of Rs 5,000 on each of them.
The court acquitted Balliudeen, Mukeedeen and Nafesar for want of evidence, public prosecutor Ravindra Singh Gaur said.
According to prosecution, the activists had gathered in Pithampur to chalk out their next major attack, and were allegedly preparing prospective assassins in training camps.
The Peethampur police had named 17 people as accused in the FIR.
In a major crackdown in 2008, the Indore police had caught 13 top SIMI functionaries from a house in Pithampur Industrial area.