Information giant VNU is under increasing pressure to ditch its planned $7 billion (€5.83bn; £3.95bn) purchase of pharmaceutical data provider IMS Health.

VNU, headquartered in the Netherlands and best known as owner of Nielsen Media Ratings in the US, has been told by major shareholders they oppose the acquisition and urge the company to pursue other options to secure its future.

However, if it dumps the deal VNU could itself become vulnerable to takeover or being sold for its constituent parts.

Meantime, prowling the perimeters of VNU is a consortium of four private equity firms, including 'Barbarian at the Gate' Kohlberg Kravis Roberts and Blackstone Group, which approached and was rejected by VNU before the IMS deal was announced.

The company's shareholders began voicing their concerns last month [WAMN; 30-Sept-05] over what they perceive as a risky merger of VNU's consumer products and TV market research services with IMS' similar resource for the global pharmaceutical industry.

VNU has explored ways to address these fears, including the sale of large assets, increasing stock buyback and even replacing ceo Rob van den Bergh. But these offers have been deemed unacceptable by investors.

Data sourced from Wall Street Journal Online; additional content by WARC staff