Companies like Apple have this routine of filing and receiving technology patents but that is only there is to it.
But on Wednesday, in a filing in U.S. District Court in San Diego, Apple revised its answer to Qualcomm's complaint with accusations of its own.
Qualcomm in July accused Apple of infringing several patents related to helping mobile phones get better battery life.
Apple claims in its suit that Qualcomm's Snapdragon 800 and 820 processors - used in Samsung and Google phones - infringe Apple's patents.
Qualcomm accuses Apple of violating 16 of its patents including power-saving tech and camera autofocus in devices from the iPhone 7 to the new premium iPhone X.
Reuters reports that the feature allows the smartphones' processor to draw the minimum power needed at the time by turning off unnecessary cores.
This is of course a countersuit, dating back to a lawsuit Qualcomm filed against Apple on exactly the same grounds. (NASDAQ: INTC), a move that led Qualcomm to file a complaint with the U.S. Federal Trade Commission to ban importing iPhones using the Intel chips due to the alleged patent infringements.
This only the latest part in the drama between the two, as originally Apple sued Qualcomm for $1 billion in January for not paying certain royalties. In a related suit, Qualcomm sued the contract manufacturers that make Apple's phones, but Apple joined in to defend them.
The source notes there's also a matching complaint from Qualcomm with the US International Trade Commission that would ban imports, and thus sales, of the iPhone X and other models over five of the patents. That's something Android device makers won't necessarily like, even though many of them already sided with Apple in its fight against Qualcomm.