On Assignment Inc., a Calabasas temporary staffing firm, said it has agreed to buy Apex Systems Inc. for $600 million in cash and stock.
On Assignment provides staffing services for the technology, healthcare and life sciences industries. Apex specializes in information-technology staffing and services.
The acquisition would create the second-largest IT staffing firm in the country with combined revenue of $1.3 billion, the companies said. IT would constitute 70% of revenue.