Fortescue Metals Group (FMG) founder and chairman Andrew Forrest has become the biggest shareholder in Australian shipbuilding group Austal.

The mining and vessel chartering billionaire, a leading proponent of decarbonisation in shipping, has amassed a stake of 15.39% since March.

This holding is now worth AUD 140m ($94m).

The previous biggest investor was Austal chairman John Rothwell, a former chief executive of the group, with 9%.

The investment has been made through Tattarang Ventures, Forrest’s investment company.

In March, Tattarang revealed an 8.1% stake but bought more stock to reach 13.% in June.

The investment has already made Forrest a healthy profit, with the share price rising 24% since July.

But the FMG boss shows no sign of selling out and Australian media outlets have speculated that Austal is “in play” in terms of a takeover.

Forrest has not commented.

The share deals could be seen as another demonstration of Forrest’s interest in zero-carbon shipping and shipbuilding.

Ammonia plan

Earlier this year, FMG bought a platform supply vessel (PSV) for conversion to run on green ammonia.

Domestic shipowner MMA Offshore said its 3,100-dwt MMA Leveque (built 2010) had gone for $7.75m.

The ship is being acquired by Fortescue Future Industries (FFI), which will transform the vessel into a dual-fuel unit with the objective of running it almost completely on green ammonia.

The miner announced earlier in 2021 that it intended to retrofit its fleet of ore carriers to use green ammonia as part of efforts to achieve net-zero Scope 3 emissions by 2040.

Forrest has said the group will be converting all its 100 ships on the water well before 2030.

Austal also operates shipyards in the Philippines, Vietnam, and in the US.

The shipbuilder posted a 14% fall in profit in the first half of its financial year to AUD 45.1m.