Apple has accused Imagination Technologies of making "misleading" claims in its accounts of the two company's acrimonious break-up over the past year.
Back in April, Imagination announced that Apple planned to stop licensing its designs within '15 to 24 months' in favour of developing its own graphics chips. This shift came as a major blow to the chip designer as it relies on contracts from Apple for about half of its revenue.
Imagination, for its part, made veiled threats of legal action if Apple were to infringe any of Imagination's intellectual property.
"Apple has not presented any evidence to substantiate its assertion that it will no longer require Imagination's technology, without violating Imagination's patents, intellectual property and confidential information.
"This evidence has been requested by Imagination but Apple has declined to provide it," Imagination said at the time, just weeks before launching a dispute resolution procedure with Apple.
"Further, Imagination believes that it would be extremely challenging to design a brand new GPU architecture from basics without infringing its intellectual property rights, accordingly Imagination does not accept Apple's assertions."
Apple has this week hit back at the company and accused it of putting out "inaccurate" and "misleading" statements in relation to the break-up.
It claims that, in 2015, it told Imagination that it would no longer be buying its latest technology, and the following year notified the firm that it was initiating a clause in its contact that allowed it to pay a lower royalty rate for using a smaller amount of intellectual property.
By February of this year, Apple claims, it told Imagination it was ending the relationship altogether and would no longer be making any royalty payments as early as 2018.
Imagination, however, this week told investors that it hadn't been made aware of Apple's plans until the end of March this year.
"We're disappointed in their response, which has been inaccurate and misleading," Apple said in a statement given to Bloomberg.
"We began working with Imagination in 2007 and stopped accepting new IP from them in 2015. After lengthy discussions, we advised them on February 9 that we expected to wind down our licensing agreement since we need unique and differentiating IP for our products.
"We valued our past relationship and wanted to give them as much notice as possible to adapt their future plans."
Apple's response unlikely will go down well with Imagination, which last month put itself up for sale. The company claims that "it has received interest from a number of parties for a potential acquisition of the whole group".
Cotton seedling freezes to death as Chang'e-4 shuts down for the Moon's 14-day lunar night
Fortnite easily out-earns PUBG, Assassin's Creed Odyssey and Red Dead Redemption 2 in 2018
Meteor showers as a service will be visible for about 100 kilometres in all directions
Saturn's rings only formed in the past 100 million years, suggests analysis of Cassini space probe data
New findings contradict conventional belief that Saturn's rings were formed along with the planet about 4.5 billion years ago