The Rieber family of Norway is aiming to buy 100% control of its GC Rieber Shipping operation.

The investment company GC Rieber has launched an offer for the remaining stock in the Oslo-listed shipowner after building its stake to 91.56%.

The parent bought 12.68m shares to add to its previous holding of 76.84% in GC Rieber, which is making a move into offshore wind farm vessels.

The offer is being made at NOK 8.80 per share, against a price of NOK 4.91 in Oslo on Monday.

The market cap is NOK 423m ($38.1m).

GC Rieber’s chairman is GC Rieber chief executive Jan Roger Bjerkestrand.

He has not participated in the board’s consideration of the offer.

Directors have concluded the offer is fair and will “reflect the financial and strategic value of the company”.

The shipowner’s CEO has Einar Ytredal has sold his 41,325 shares and chief operating officer Oystein Dalland Kvale has pledged his 27,560 shares.

The majority of the private shareholders of parent GC Rieber are fourth and fifth-generation members of the family of founder Gottlieb Christian Rieber.

Expansion in wind on the cards

TradeWinds reported in June that the shipping subsidiary was planning further growth for its new wind shipping venture Windkeeper.

The company has two firm service operation vessels being built at Turkey’s Cemre Shipyard, with two options attached.

GC Rieber used to be a seismic survey ship owner, but today has only a tug and a crew boat operational.

Ytredal told TradeWinds: “The Windkeeper ordering is progressing well.”

“The options for the two other vessels are not declared. The deadline for the first option is in the fourth quarter of 2023,” he added.

The “groundbreaking” ships are due from the first quarter of 2025.

The total investment so far is about €110m ($120m).

Earlier this year, GC Rieber said it was handing over a $51m stake in its seismic survey vessel spin-off to investors.

Shareholders were to receive shares totalling 8.5% in seismic survey shipowner Shearwater GeoServices as an extraordinary dividend.

The company had 5m shares in Shearwater, which has been preparing for an IPO in Oslo.