Hyperlink allows users to click on an online object and trigger associated items elsewhere on the Web. Early in 2000, after discovering in a routine check that it owned the patent for the hyperlink, BT wrote to 17 US ISPs, including Prodigy, asking them to pay for the privilege of using the technology through licensing agreements.
The suit filed against Prodigy – which claims to be the first commercial US ISP there – is the first BT has filed to protect its hyperlink patent.
Last year, BT also hired technology development and licensing company Scipher to broker licensing agreements with the US ISPs.
Internet founding father Tim Berners-Lee is generally credited as writing in the 1980s the underlying hyperlink protocols - including HTTP, or hypertext transfer protocol - for what later became the World Wide Web.