Investment in specified long-term bonds secures capital gains exemption, subject to a six-month window and five-year lock-in. Capital gains on transfer of long-term land or building may be exempt if the assessee invests the capital gain in specified long-term bonds within six months of transfer, subject to an annual aggregate investment ceiling and issuance/date-based eligibility. Such bonds carry a five-year lock-in; if transferred, converted to money, or charged within that period the previously exempted gain becomes taxable in the year of that event. Investments in these bonds are excluded from claiming overlapping deductions under other deduction provisions for the relevant assessment years. The exemption is limited to the lesser of the capital gain and the cost of the bonds acquired.