Former Abbott Laboratories employees filed a lawsuit Monday accusing the pharmaceutical giant of spinning off its hospital products division--and the division’s 10,000 U.S. workers--into a new standalone company in order to unload costly benefit obligations.The complaint alleges that Abbott and spinoff Hospira Inc. interfered with workers’ rights to receive employment benefits. Specifically, the lawsuit alleges that the companies violated the federal Employee Retirement Income Security Act of 1974, commonly known as ERISA.