The €168m pension fund of Ardagh Glass Nederland is seeking to liquidate and join the €21bn PGB on 1 January.
Unions said they would support the plan if the company maintains average salary arrangements.
In a letter to Ardagh, they said they opposed any shift towards a collective defined contribution arrangement.
Unions also called on the company to pay all costs of the transfer and said the pension fund should grant all participants and pensioners indexation if the coverage ratio still exceeds PGB’s funding.
Coverage at the Ardagh scheme, as of the end of June, stood at 98.6%, while PGB’s stood at 97.5%.
The company and union De Unie said negotiations were ongoing but declined to provide details on the outstanding issues.
Ardagh Glass, in a newsletter for its workers, argued that the pension fund was “too small to keep complying with legislation and legal rules for the scheme’s board against reasonable costs”.
In its 2015 annual report, the pension fund reported costs for pensions administration of €273 per participant.
Over the same period, it spent 0.24% on asset management and 0.05% on transactions.
A working group at the scheme concluded that joining PGB was its best option, in part because PGB’s pension plan is quite similar to the arrangements of the Ardagh scheme.
In other news, the €1.5bn pension fund of Gasunie has awarded Cardano a €300m government bond mandate, managing inflation-linked bonds (ILBs) and interest derivatives in its matching portfolio.
Until now, the scheme’s government bonds and ILBs had been managed by Lombard Odier, with the pension fund managing the derivatives in-house.
The Gasunie scheme said it selected Cardano because of its expertise on risk management, as well as its integrated deployment of bonds and derivatives.