Section 3
SEC. 3. Subsection (a) of section seven of Commonwealth Act Numbered One hundred eighty-six, as amended by Republic Act Numbered Six hundred sixty, is further amended to read as follows: "SEC. 7. Additional premiums.—(a) For the amount of annuity corresponding to the services rendered by an employee prior to June sixteen, nineteen hundred fifty-one, his employer as of the date of his retirement shall pay under such rules and regulations as the System may prescribe the necessary additional amounts or premiums: Provided, That this obligation may not be paid in installments without the prior approval of the System if the employer is a corporation owned or controlled by the Government."