PLX Technology (PLXT -15.4%) tumbled and IDT (IDTI +4%) spikes higher on news the FTC has filed a complaint challenging the companies' planned merger. The agency is concerned about the 85%+ share the combined company would have in the PCI-Express switch market. Back in April, IDT agreed to buy PLX for $3.50 in cash and 0.525 shares for every PLX share outstanding.