Qualcomm's legal spat with Apple is growing nastier; the chip giant now claims Apple tried to give rival Intel a sneak peek into Qualcomm's trade secrets.

In a Wednesday lawsuit, Qualcomm says a software license agreement the two companies signed in 2010 gave Apple access to Qualcomm's software source code. This access was "unprecedented," according to Qualcomm, but Apple insisted it was necessary and Qualcomm agreed.

However, Qualcomm alleges that Apple tried to share the confidential information with Intel, which now supplies a baseband modem found in iPhones.

In July, Apple sought details from Qualcomm on implementing an "interprocessor" communication protocol—information that is considered highly sensitive and contains company trade secrets, according to the lawsuit. When making the request, Apple sent out a message that CC'd an Intel engineer.

The lawsuit also claims Apple did little to stop the valuable Qualcomm information from being shared with Apple engineers who were working with Intel.

Qualcomm says the move violates its software agreement; it is seeking damages from Apple.

The lawsuit is part of an ongoing legal battle between the two companies. Apple claims the chipmaker is charging too much for its patents. But Qualcomm has countersued, accusing the iPhone maker of violating its patents and engaging in unfair business practices.

So far, none of the companies involved in Wednesday's lawsuit, including Intel, have commented. But the escalating legal action is taking a toll on Qualcomm's financial performance—a 90 percent year-over-year drop in quarterly profit, the company CEO said on Wednesday.