Market sources: US side said signatories to letters of intent include Kepler, Multibeam and Extropic.

HSBC analyst Daragh Maher said markets have already priced in some Fed tightening; if the Fed holds rates the dollar could weaken. He said at least three Fed voters would need to back a hike to blunt the dollar's initial decline. Conversely, an actual hike would likely provoke an initial dollar rise larger than any initial drop from a hold. "If the pace of hikes is faster than expected, it will force markets to consider whether this is the first of a series," he added. He expects a pause would not materially alter expectations for a September hike.

Tokyo Electron said its buildings sustained no major damage following the earthquake.