The Bar council of India made certain rules in this regard under the Advocates Act, 1961. A legal practitioner, while he is on the rolls of a high court, is not entitled to enter into any business or service without permission of the court. If he does, disciplinary action may be taken against such person. There are however a few exceptions to this rule.
Section VII of the rules provides for the restriction on other employments:
47. An advocate shall not personally engage in any business; but he may be a sleeping partner in a firm doing business provided that in the opinion of the appropriate State Bar Council, the nature of the business is not inconsistent with the dignity of the profession.
48. An advocate may be Director or Chairman of the Board of Directors of a Company with or without any ordinarily sitting fee, provided none of his duties are of an executive character. An advocate shall not be a Managing Director or a Secretary of any Company.
49. An advocate shall not be a full-time salaried employee of any person, government, firm, corporation or concern, so long as he continues to practise, and shall, on taking up any such employment, intimate the fact to the Bar Council on whose roll his name appears and shall thereupon cease to practise as an advocate so long as he continues in such employment.
50. An advocate who has inherited, or succeeded by survivorship to a family business may continue it, but may not personally participate in the management thereof. He may continue to hold a share with others in any business which has descended to him by survivorship or inheritance or by will, provided he does not personally participate in the management thereof.
51. An advocate may review Parliamentary Bills for a remuneration, edit legal text books at a salary, do press-vetting for newspapers, coach pupils for legal examination, set and examine question papers; and subject to the rules against advertising and full-time employment, engage in broadcasting, journalism, lecturing and teaching subjects, both legal and non-legal.
Rule 47, which provides for an advocate to not personally engage in any business; but allowing him to be a sleeping partner in a firm doing business, subjected to certain mentioned conditions, serves as reply to your query.