Catalyst has acquired a minority interest in Bhagwan, believed to about a 40 per cent shareholding.
Bhagwan, headed by managing director Loui Kannikoski, will use the proceeds to pay down debt and prepare for future growth.
“This partnership with Catalyst will provide a step change in the growth of our company and allow us to better meet the needs of our customers,” Mr Kannikoski said.
The Catalyst deal comes 12 years after Mr Kannikoski and his family decided to move out of the crayfishing industry and focus on the oil & gas sector.
The business has grown rapidly since then, and now has a fleet of 50 vessels and annual turnover of about $120 million.
It employs about 400 workers offshore and has nearly 50 administrative and support staff.
The Kannikoski family will retain a majority shareholding in the business, but will cede a majority of board seats to Catalyst.
The company will be chaired by Catalyst representative Anthony Wooles, who is also making a personal investment in Bhagwan.
Catalyst managing director John Story and its Perth-based executive director Aaron Hood will also join the board, along with Mr Kannikoski and commercial manager Darren Kollin.
Catalyst was advised by KPMG and Clayton Utz.
It said Bhagwan will continue to be supported by Bankwest.
(This week’s print edition of WA Business News will feature a detailed story on this deal and other private equity moves in WA.)