The combined acquisition sees it pay a total of £4.1m for Zambeasy, which is behind Top-Consultant.com, and Office Recruit, which publishes Officerecruit.co.uk.
The two acquisitions by Associated New Ventures, a division of Daily Mail-owner Associated Newspapers include the estimated earn-out payments and follow the acquisition of by DMGT in March 2004 for £35m.
The group has since launched three niche sites for the pharmaceutical sector with , and .
specialises in jobs for management consultants and publishes vacancies for secretaries, administrators, customer service and telesales, accounts and legal clerks.
Andrew Hart, managing director of Associated New Ventures, said: "We've seen Jobsite go from strength to strength and it was our aim to find related profitable companies to sit within Jobsite as part of an expanding Jobs division."
The two businesses will continue to be run by their current management teams and will retain their brand names, strengthening Jobsite's offering for recruiters and jobseekers.
Keith Potts, managing director of Jobsite, said: "Online recruitment is a flourishing and profitable market. These acquisitions fit well with our strategy to build specialist vertical sites which complement Jobsite's strengths."
In May DMGT posted profits before tax of £114.5m for the six months to April this year, an increase of 7% on figures for last year.
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