In all probability the corporates want to make such donations as part of their CSR requirements. At the bare minimum, you should verify whether the companies have been duly incorporated, who the directors are, whether the company has been conducting its business and has the necessary funds, and whether the company has authorized the release of funds through a board resolution. If an NGO gets itself registered under section 80G then the person or the organisation making a donation to the NGO will get a deduction of 50% from his/its taxable income. The NGO has to apply in Form No. 10G As per Annexure-29 to the Commissioner of Income Tax for such registration. Normally this approval is granted for 2-3 years. Feel free to get in touch if we could be of any further assistance to you.