On Monday, legal research platform ROSS filed a counterclaim arguing that Westlaw’s legal research dominance is fueled by Thomson Reuters’ alleged anticompetitive tactics. The filing was in response to Thomson Reuter’s lawsuit lodged in May that accused ROSS of scraping Westlaw’s proprietary data for content.

ROSS alleged in its filing that Westlaw’s status as “king of legal search” was a product of “exclusionary and [an] anticompetitive course of conduct to maintain its monopoly and restrain trade.” ROSS wrote it would show Westlaw “used anticompetitive sales and licensing regimes supported by a web of sham copyrights and intimidation tactics to crush potential rivals like ROSS.”