Apple has lost its appeal against a UK ruling that Samsung had not infringed its design rights.
A judge at the High Court in London had originally ruled in July that the look of Samsung's Galaxy Tab computers was not too similar to designs registered in connection with the iPad.
He said at the time that Samsung's devices were not as "cool" because they lacked Apple's "extreme simplicity".
Apple still needs to run ads saying Samsung had not infringed its rights.
The US firm had previously been ordered to place a notice to that effect - with a link to the original judgement - on its website and place other adverts in the Daily Mail, Financial Times, T3 Magazine and other publications to "correct the damaging impression" that Samsung was a copycat.
The appeal judges decided not to overturn the decision on the basis that a related Apple design-rights battle in the German courts risked causing confusion in consumers' minds.
"The acknowledgment must come from the horse's mouth," they said. "Nothing short of that will be sure to do the job completely."
However, they added that the move need not "clutter" Apple's homepage as it would only have to add a link entitled "Samsung/Apple judgement" for a one-month period.
A spokeswoman for Samsung said it welcomed the latest ruling.
"We continue to believe that Apple was not the first to design a tablet with a rectangular shape and rounded corners and that the origins of Apple's registered design features can be found in numerous examples of prior art.
"Should Apple continue to make excessive legal claims in other countries based on such generic designs, innovation in the industry could be harmed and consumer choice unduly limited."
Apple declined to comment. It can still appeal to the UK Supreme Court, otherwise the ruling applies across the European Union.
Three judges were involved in the Court of Appeal review of the case.
Apple had reasserted its claim saying that the front face and overall shape of the tablets was the most important factor - rather than the overall design - because users would spend most of their time looking at a tablet's screen and holding it.
One of the judges - who noted he owned an iPad himself - explained why Apple had lost the appeal in his ruling.
"Because this case (and parallel cases in other countries) has generated much publicity, it will avoid confusion to say what this case is about and not about," wrote Sir Robin Jacob.
"It is not about whether Samsung copied Apple's iPad. Infringement of a registered design does not involve any question of whether there was copying: the issue is simply whether the accused design is too close to the registered design according to the tests laid down in the law."
"So this case is all about, and only about, Apple's registered design and the Samsung products."
Sir Robin noted that Samsung's decision to place its logo on the front of its devices distinguished them from Apple's registered design which said there should be "no ornamentation".
He also highlighted the fact that the sides of the iPad's design - which featured a "sharp edge" - were significantly different from those of the Galaxy Tabs.
In addition, Sir Robin wrote that Samsung's designs were "altogether busier" with a more varied use of colour on the devices' rear and their inclusion of a thicker section to house a camera.
Apple has now lost a series of lawsuits against Samsung based on the design of their tablets.
These include cases in the Netherlands, Australia and US - despite sometimes winning temporary sales bans.
However, the California-based company has been more successful with other claims.
Most notably a US jury proposed Samsung should pay Apple a $1.05bn (£650m) fine for infringing several software patents, and the look and feel of the iPhone. Samsung is appealing the verdict.