The Hollywood movie industry has ended its attempts to bring charges of DVD piracy against Norwegian Jon Johansen.
Movie firms moved to sue DVD descrambler
Mr Johansen, known as DVD Jon, was acquitted in December but the US film industry was expected to appeal.
He was charged with aiding copyright breakers by writing the DeCSS program that allows DVDs to be played on PCs running the Linux operating system.
But the appeal deadline has passed without a reaction from film makers - bringing the court case to an end.
The four-year legal battle started when Mr Johansen was 15 and wrote the program that got round the content scrambling system built into DVDs that helps to stop pirates copying them.
The DeCSS program was widely distributed online when it first appeared in 1999 and the legal wrangle over it has turned Mr Johansen into something of a folk hero.
In his defence Mr Johansen argued that DeCSS was only helping him watch the DVDS he already owned on his Linux PC.
The Motion Picture Association of America did not agree and pressed for piracy charges.
The case was widely seen as a test of the film industry's ability to police what happens to its products.
However, Norwegian courts resisted the pressure and acquitted Mr Johansen on two occasions of the charges of aiding copyright breakers.
The most recent acquittal took place on 22 December in a Norwegian appeals court.
The Norwegian police could have taken the case to the country's Supreme Court but has now decided not to pursue the prosecution any further.
"I am pleased with the final outcome and so is my client," said Halvor Manshaus, lawyer for Mr Johansen.
"This brings this case to a final end, following acquittals in both the district court and the appeals court," he said.