Rambus (RMBS) is rolling and calls are seeing heavy trading Monday. Shares are up $1.58 to $11.52 and caught bid on heavy volume about 45 minutes ago. Briefing notes the move coincided with a Bloomberg story about a possible settlement between RMBS and European Union regulators over accusations it sought “unreasonable royalties.” Options traders are reacting as well, with very heavy trading seen in RMBS May calls with strike prices between 10 and 15.