Molyneux acquired circa 617,000 shares for $15,500, which followed on from his December purchase of 500,000 shares for $14,000.
He now holds over 2.6 million shares.
Molyneux is also the chief executive office of uranium producer Paladin Energy (ASX:PDN).
Argosy is focused on the Rincon joint venture lithium project which it intends to fast track to production of clean commercial grade lithium carbonate.
Rincon is located in the world’s most prolific lithium producing region of Argentina.