Business news in brief

SEPTA formally rejected binding arbitration of its contract dispute with commuter railroad engineers and electricians, moving a step closer to a possible strike that would halt Regional Rail service early next year. In letters to Daniel Rainey, chief of staff of the National Mediation Board, SEPTA labor-relations chief Stephanie K. Deiger said the transit agency "respectfully declines the proffer of arbitration." The Brotherhood of Locomotive Engineers and Trainmen, Division 71, which represents about 220 SEPTA engineers, and the International Brotherhood of Electrical Workers, Local 744, which represents about 200 electricians, had agreed to arbitration. The next step, under federal railroad labor laws, is for the mediation board to release the parties from mediation. That would start a 30-day "cooling off" period and a 240-day dispute-resolution period required before a strike or lockout would be permitted. - Paul Nussbaum

Sikorsky Aircraft was selected to build the next fleet of Marine One helicopters for the Office of the President and will perform initial assembly of the six aircraft at its facility outside Coatesville in Chester County. Sikorsky, a subsidiary of United Technologies Corp., won a $1.24 billion contract for the specially fitted Marine One versions of its S-92 helicopter. Connecticut-based Sikorsky says 10 countries currently fly dual-engine S-92s for head-of-state missions.

- Reid Kanaley

Ametek Inc., the Berwyn maker of electronic instruments, raised its quarterly dividend to 9 cents per share, from 6 cents - a 50 percent increase - payable June 30 to shareholders of record June 16. Ametek, an S&P 500 index component, on Tuesday reported record first-quarter sales and earnings. It had 2013 sales of $3.6 billion. Shares fell 16 cents, or 0.3 percent, to $52.97. - Reid Kanaley

Timothy Geithner says in a new memoir he repeatedly offered to resign as Treasury secretary in the aftermath of the financial crisis and at one point suggested Hillary Rodham Clinton be among those considered to replace him. President Obama rebuffed Geithner's suggestion, and he remained at Treasury until 2013. Geithner's memoir will be published next week. The Associated Press bought an early copy. Geithner tells of his offers of resignation in Stress Test, which explores his turbulent four years at Treasury during the financial crisis. - AP