MUMBAI: Non-banking financial services firm Srei has filed bankruptcy petitions against three of four companies that held and sold Viom Networks shares on its behalf. The applications for insolvency against Right Tower, Resurgent Infratel and Confident Solar came up for hearing on Monday and were admitted by National Company Law Tribunal as legitimate cases. The cases will be heard on October 24, when these companies and Srei Infrastructure Finance will need to present a resolution plan. A person close to the developments said an insolvency application had also been filed for the fourth company, Optimum Infratel, but ET could not independently verify this. The Srei group was represented by local boutique law firm MKB & Associates, as per a listing on the website of the tribunal. The law firm did not comment. The Srei group did not respond to ET's queries till press time Tuesday. Listed Srei Infra held 11% of Viom directly while the remaining 7% was held through the four entities.