Monaco investment fund HAL Holding is making a €2.26bn ($2.5bn) offer to buy the rest of the stock it does not already own in giant Dutch contractor and shipowner Boskalis.

HAL is the biggest investor with a 46.5% stake currently, and has been a shareholder since 1989.

But the fund believes Boskalis’ Amsterdam listing offer limited added value for the group and does not outweigh the costs involved.

The offer price of €32.5 per share values Boskalis at €4.2bn