Is it an obligation to declare mutual funds or share based assets in?
No there is no obligation to declare specific holdings of mutual funds or share based assets. However if you are filling up a Business/Profession return you are expected to prepare a balance sheet and profit and loss account. The balance sheet will have the sum total of investments. Also if you are having total income above Rs. 50,00,000/- you are expected to disclose some details of your assets but not the specific names etc you will just be stating say Investments in Shares and Mutual Funds - Total Rs as on 31.03. of the relevant FY.