The firm claims that the new database is the UK's most comprehensive in terms of its coverage, containing 3.5m business decision-makers, who Mardev claims are responsible for 96% of all UK business spend.
Nick Martin, Mardev's managing director, said: "We have made a significant investment in our online service. As well as the spend on DecisionMaker, we have also been listening to customer feedback and as a result have made a range of improvements to the online service, making it even easier to use."
The new version of customersearch.net now includes the ability to select targets using drive-time/distance, a function Mardev believes to be unique to the marketplace. It also gives increased search speed, with most data searches taking under five seconds, and contains 400,000 new records.
Martin said: "We are now confident that customersearch.net is the most comprehensive online database of its kind. No other is so easy and quick to use and that, added to the other improvements we have made, make it the market leader. In fact, it's so easy to use, we don't even need to offer a customer helpline."
Separately, Mardev has conducted research that has found the vast majority of small British firms view the Corporate Telephone Preference Service, which enables businesses to register their right not to receive cold sales calls, as a restriction on trade.
The firm is hosting a debate on the issue on 27 March at the English Speaking Union in Mayfair, called: "Is the CTPS Working?" Speakers include Mardev's Nick Martin; John Price, the chairman of the DMA's Telemarketing Council; Robert Bond, a specialist in intellectual property and technology law; and Claire Hobson, head of UK telecom policy at the Department of Trade and Industry.
Mardev is owned by Reed Elsevier and has offices in Western Europe, Eastern Europe, North and South America, Asia and Australia.