Ivan Sinanovič was born in 1929 in Slovenia. He was one of the leading individuals of the Yugoslav Cominformist movement in Prague in the 1970s. Sinanovič was admitted to the central committee of the new Communist Party of Yugoslavia (CPY), which was illegally founded in 1974 by various Yugoslav emigrant groups from across Europe. He operated the so-called Prague cell of the new CPY.

Sinanovič kept the leaflets produced by the Prague cell in the period 1971–76 to document its activity, and thus he is considered as the founder of the Yugoslav Cominformists in Prague collection.

Sinanovič was a labourer by profession and thus was not suspected of having been the leaflets’ author as he was not highly educated. As he was the least suspicious among Yugoslav Cominformists in Prague, being a member of the Communist Party of Czechoslovakia and a Czechoslovak citizen, at the time, the leaflets were considered to be the most secure with him. 

In 2011, Sinanovič handed the collection over to the Czech historian Ondřej Vojtěchovský.