New Delhi, April 16 -- Mehli Mistry, a close associate of late tycoon Ratan Tata, has challenged his ouster from Sir Dorabji Tata Trusts (SDTT), the largest among Tata Trusts, and requested the appointment of an administrator to run the philanthropic entities behind the sprawling Tata Group of companies.

In an affidavit filed before the Maharashtra charity commissioner on Wednesday, Mistry challenged the votes cast by Venu Srinivasan and Vijay Singh that led to his ouster in October; questioned Tata Trusts chair Noel Tata's objection to reappointing N. Chandrasekaran as chair of Tata Sons; and highlighted what he claims is a procedural flaw in the appointment of Noel as the Trusts chair.

On 24 February, the Tata Sons board deferred a de...