Trust income benefit restrictions limit tax-exempt status where trust funds benefit founders, authors, contributors or their relatives. The amendment substitutes sub clause (ii) of clause (b) in section 13 to treat as disqualifying any instance where trust income or property is used or applied, directly or indirectly, for the benefit of the author, founder, substantial contributor, or their relatives, including members or relatives of a Hindu Undivided Family; a proviso limits the section's operation where the benefit to a relative in the previous year does not exceed a specified proportion of the trust's income, by confining the section's effect to the part of income represented by that benefit and its value.