"Based on the available data, neither Banionis nor Sondeckis secretly collaborated with the KGB structures," Algimantas Urmonas, the commission's chairman, told BNS.
The Lithuanian Genocide and Resistance Research Center (LGRRC) said last January that the two renowned men, both deceased now, had been entered on a register of KGB agents during Soviet times.
Historians say, however, that the register contains inaccuracies and should be viewed in conjunction with other historical sources.
According to Urmonas, the Lustration Commission's decision opens the way for the relatives of those mentioned to bring a legal action for defamation and ask LGGRTC to refute the published information.
The Lrt.lt news website has reported that Saulius Sondeckis Junior, the conductor's son, does not rule out turning to court, but has made no decision yet.
Raimondas Banionis, the actor's son, also says that the family have not yet decided on their next steps.
The five-member Lustration Commission assesses, based on available data, the activities of secret collaborators with the Soviet secret services and publishes the name of those who failed to confess by an established deadline.
The register published by LGGRTC contains a total of almost 1,700 archival dossiers of alleged KGB agents.