Germany’s Hartmann Group has exercised an option for a seventh 3,500 teu containership at Taizhou Sanfu Ship Engineering, continuing its LNG dual-fuel newbuilding programme tied to US carrier Seaboard Marine.

The latest ship marks an expansion of a series launched in 2021, when Hartmann ordered three vessels with options for three more.

The new order is priced around $75m, a notable increase from the original six, which were booked at roughly $60m each.

The ships are being built to a high-specification dual-fuel design developed by German naval architecture firm HB Hunte. All seven units are to be managed by Hartmann on behalf of Miami-based Seaboard Marine, which will deploy the vessels in regional trades.

Delivery details for the latest ship have not yet been confirmed. Four newbuilds from the initial six-ship project have already been delivered, with the remaining two expected later this year and in 2026.