Definitely not true. The first LDAP implementation was published in 1993, and was worked on for a while before that internally at the University of Michigan:

http://en.wikipedia.org/wiki/Tim_Howes

The first real browser, Mosaic, was released the same year.

Eventually Howes went to Netscape, but Netscape didn't exist until 1994, and Howes didn't join them until 1996