Finnish vendor Nokia fired its counterstrike against chip giant Qualcomm on Thursday.

The pair have been locked in a bitter dispute, with Nokia maintaining that its products do not infringe either of the two Qualcomm patents named in the suit and asserting that both patents are invalid.

On Thursday, Nokia made patent counter assertions against Qualcomm, claiming its infringement of six Nokia implementation patents used in Qualcomm GSM/WCDMA and CDMA2000 chipsets.

In its own filing, Nokia concedes that the six patents are not essential for the practice of standards, “however they provide substantial benefits when used,” the company said.

Just as in its litigation filings Qualcomm has sought injunctions against Nokia, so Nokia is seeking damages and an injunction against Qualcomm.