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Director / Relative should not be employee / partner / proprietor of legal or consultancy firm which has any transaction with company / holding / subsidiary / associate exceeding 10% of gross turnover of such legal or consultancy firm, during immediately preceding 3 financial years  
Eg Legal Fees from Subsidiary 50,00,000 Gross Turnover of Legal Firm 2,00,00,000 so that is 25% then employees / partners / proprietors of such firm during immediately preceding 3 years cannot become independent director.
In Definition of Independent Director
(vi) who, neither himself, nor whose relative(s) —

(A)holds or has held the position of a key managerial personnel or is or has been an employee of the listed entity or its holding, subsidiary or associate company in any of the three financial years immediately preceding the financial year in which he is proposed to be appointed;

(B) is or has been an employee or proprietor or a partner, in any of the three financial years immediately preceding the financial year in which he is proposed to be appointed, of —
(1) a firm of auditors or company secretaries in practice or cost auditors of the listed entity or its holding, subsidiary or associate company; or
(2) any legal or a consulting firm that has or had any transaction with the listed entity, its holding, subsidiary or associate company amounting to ten per cent or more of the gross turnover of such
firm;

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