By Mike Yamamoto, managing editor of OptionMonsterShares of Rambus ( RMBS) spiked nearly 19% Monday along with bullish options activity after the company won a tentative court victory over its antitrust claims. The chipmaker traded nearly 36,500 options Monday, more than 5.5 times its average daily volume of about 6,300. The stock also saw heavy volume of nearly 9.5 million shares, more than 3.5 times the normal turnover. The shares rallied strongly after a preliminary ruling by a California court allowed the Silicon Valley company to proceed with its antitrust case against three rival memory chip manufacturers. Rambus, which provides chip technology for Sony's ( SNE) PlayStation game systems and other products, has reportedly accused Samsung, Hynix and Micron Technology ( MU) of illegal price fixing. Options traders were focused on the several May contracts, most notably at the May 12 and 13 strike prices, according to OptionMonster's proprietary tracking systems. Although the trading was lower than open interest, the number of calls bought at the two strikes (about 4,800 and 2,300, respectively) outnumbered contracts sold by roughly two to one, indicating an overall bullish sentiment. Rambus shares closed Monday up 18.7% to $11.80. The call-buying action apparently indicates that options traders believe the stock still has more potential to rise within the next few weeks until the May contracts expire.