The OM No. No.4/14/2001-P&PW (D) dated 19/9/2003 refers to the decision on the cases similar to yours with reference to Revision of pension and other attendant benefits of Central Government employees retired/retiring on IDA pay scales and opting for pensionary
benefits of combined service in Government and public sector undertakings (PSU). .
The gist of the above referred OM is reproduced below:
w.e.f. 1.1.1996 pension of all such PSU retirees
who had been absorbed in PSUs as a result of conversion and had opted for pensionary
benefits of combined service in the Central Government and the PSU as per Central
Government Rules on their absorption, shall be revised as under:-
(a) For the purpose of fixation of pension as per O.M. dated 10.2.1998, all absorbees
shall be notionally brought on to CDA scale w.e.f. 1.1.1996. for this purpose:
(i) Concerned administrative Ministries shall work out the
corresponding equivalent scale in CDA pattern, as on1.1.1986, and in
cases where it is not feasible to clearly establish the corresponding
equivalent pay scale in CDA pattern, the final decision shall be taken
by the Head of Department in consultation with the Department of
Expenditure and Department of Personnel &Training as envisaged in
para 14 of Department of Pension & P.W.’s O.M. dated 10.2.1998.
(ii) The pay and pension of the absorbees would then be notionally
determined as on 1.1.1986 as per this equivalent scale.
(iii) Notional consolidation, as on1.1.96, shall thereafter be done.
(b) For the purpose of fixation in terms of provisions contained in O.M. dated
17.12.1998, equivalent scale as on 1.1.1996 shall be worked out. Pension shall
thereafter be calculated at 50% of the minimum of that scale.
(c) The higher of the two amounts as in (a) and (b) above, shall be taken as the
revised pension on 1.1.1996 and DR on CDA pattern be granted thereon.
(d) In all those cases, where the pension of the absorbees have already been
consolidated as per O.M. dated 27.10.1997, using DR on IDA pattern, and such
consolidated pension together with IDA happens to be higher than the revised
pension plus DR arrived as above, the pensioner may be allowed to draw such
higher amount by allowing personal pension to the extent of the difference which
shall be absorbed in subsequent increase in the future.
(e) Provisions of this O.M. shall not apply to the past pensioners of this category
who have, in the past, been given a special dispensation on account of specific
orders of the courts as accepted and implemented by the government. Cases of
this nature shall continue to be governed as per the existing provisions
specifically applicable to them.
To have more ideas in this regard, you may peruse the said OM fully and then revert for more clarifications.