Apple users angered over 'staingate' screen damage
Thousands of Apple Macbook owners are campaigning for action over reported issues with the laptop's retina screen.
They are reporting "horrific stains" spreading across screens, in the forms of spots and patches.
Phi Chong, a software engineer, told the BBC he has had to replace his screen twice in the last two years. He said he had been told Apple would not carry out further screen repairs.
The firm told the BBC users should contact its Apple support centre.
One Macbook repair specialist indicated that this was not a common problem.
But users who have been affected are concerned they will face expensive service fees once their warranties and/or extended AppleCare protection plans expire.
"My last screen replacement had its anti-reflective coating start peeling off within a month," said Phi Chong.
"I'm worried it will start peeling again after my AppleCare has expired."
A website called "Staingate" has been set up by a group unhappy with Apple's response.
Some of them say they have been told they will have to pay $800 (£519) for repair work, the Staingate website states.
A Facebook group formed by people experiencing problems with their Macbook screens has 1,752 members, and Staingate claims to have been contacted by more than 2,500 people so far.
US legal firm Whitfield Bryson & Mason has contacted the Facebook group offering to investigate.
The group has also set up a petition on the Change.org website which asks Apple chief executive Tim Cook to "take immediate action" to address the issue.
Some people say problems with the screen can start appearing within a few months of purchasing the laptops, with the 13in (33cm) screen version retailing at £749 - £999 ($1,181 - $1,575) on the Apple UK website.
While many people on the Facebook page are reporting that Apple stores around the world - including in Berlin, Hong Kong, Jersey and New Zealand - are agreeing to carry out free screen repairs outside the warranty period, others said they had been told it was "cosmetic damage", which is not usually covered.
Apple has not confirmed whether there is an issue with the screens, or what might be causing the damage.
Its 2013 models seem to be worst affected, but there are online forums discussing the problem dating back to 2009.
"Customers who experience problems with their Apple products should contact AppleCare," a spokesperson told the BBC.
AJ Forsythe, founder and chief executive of the Silicon Valley-based screen repair firm iCracked told the BBC it was not an issue that had come to his company's attention in the 11 countries in which it operates.
"We generally see that when people buy a $2,000 computer or a £700 iPad they take really good care of it for the first couple of months and then it becomes an extension of their lives," he said.
"It's not necessarily the user's fault... but it's incredibly hard to build a product that can withstand millions of real-world usages.
"I'd be interested to see what happens on the manufacturer's side."