The new partners will join founder and chairman Willem Kooyker as owners of the firm.

New Jersey-based investment manager Blenheim Capital Management has appointed Thomas Kopczynski, James Wohlmacher, Gus Rossi, and Terence Kooyke as partners.

The new partners join its founder and chairman Willem Kooyker as owners of the firm, the company said in a statement.

Kopczynski is senior managing director and head of commodities trading and research. He joined the firm in August 1993 and oversees all trading staff and research personnel.

Wohlmacher is a senior managing director, chief operating officer and chief risk officer. He joined the company in May 2005 from New York-based hedge fund manager Hamilton Investment Management.

Rossi is a senior managing director and chief financial officer. He joined Blenheim in April 2006 from hedge fund administrator DPM Mellon. He is responsible for financial matters at the firm.

Terence Kooyker is a senior managing director and senior portfolio manager. He joined the company in October 2007 as a research analyst and trader before taking up his current role.

“I am delighted to welcome Tom, Jim, Gus, and Terence as partners,” said Willem Kooyker. “These appointments recognize their long and valuable commitment to Blenheim and the substantial contributions they have made in service to our clients over many years. I have great confidence in their ability to help me make Blenheim a leading alternative investment firm for a new generation of investors. I also know that they measure themselves against the standards of excellence that have always guided the firm.”