Apple shares rose 2.3% to $678.68 in early trading on Wall Street, reports The BBC.
Earlier, Samsung sent a memo to staff hitting out at what it called the “abuse of patent law”.
Shares in Samsung fell 7% in Seoul in Monday trading, their biggest one-day fall in almost four years.
On 24 August, a US court ruled that Samsung had infringed Apple patents for mobile devices in one of the most significant rulings in a global intellectual property battle.
Samsung said it would be appealing against the verdict.
“We initially proposed to negotiate with Apple instead of going to court, as they had been one of our most important customers,” the company said its memo to staff.
“However, Apple pressed on with a lawsuit, and we have had little choice but to counter sue, so that we can protect our company.”
It said that the US court’s verdict contrasted “starkly” with decisions made in other countries, including the UK, the Netherlands and Germany.
“History has shown there has yet to be a company that has won the hearts and minds of consumers and achieved continuous growth, when its primary means to competition has been the outright abuse of patent law, not the pursuit of innovation,” the memo said.
“We trust that the consumers and the market will side with those who prioritise innovation over litigation, and we will prove this beyond doubt.”
One of the biggest concerns for Samsung is whether Apple will now target the Galaxy S3, which was not included in the recent trial, as it focussed on older products.
The flagship product is Samsung’s best selling smartphone and if it is included in a US ban on sales that would give Apple a major advantage in the market, analysts said.
