A free Internet service will be launched by the Patent Office on July 31 to enable users to rummage through some 2 million trademarks that have already been registered or applied for, officials said Thursday.

The move will help business owners register their trademarks without fear of duplicating those that already exist.

The new service, which the Patent Office claims is the first of its kind in the world, is designed to provide time for business owners to check on both existing and pending trademarks at administrators' windows, they said. In the future, business owners may be able to register trademarks through the Internet, once administrators create a security system, the officials said.