The deal for John Laing Integrated Services (JLIS), which has a turnover of almost £65 million, was unconditional and took place on 18 October 2013.
All staff currently employed in JLIS have transferred to Carillion, who will add 1,500 people to its staff.
Commenting on the disposal, Adrian Ewer, Chief Executive of John Laing, said:
'Our decision to dispose of JLIS underlines our commitment to our principal investment and asset management activities. JLIS has made significant progress over the last few years, but it no longer fits within our core strategy. We are confident that under its new ownership, the business will see future growth within the public sector and benefit from being a part of an integrated support services company.'
The disposal underlines John Laing's continued strategic focus on its core business of bidding for, investing in and managing infrastructure projects.
Following the sale, John Laing now employs a total of 222 staff in its focused investment management divisions.
Earlier this year, John Laing reorganised itself into three core divisions to reflect the changes in its principal target infrastructure markets: