From waiters to high-tech freelancers, workers say they are misclassified as independent contractors so that businesses can avoid paying benefits. They are fighting back in court, and Congress may be about to intervene as well.

In addition to the high-profile suit against Microsoft Corp., in May a group of California agents for Allstate Corp. sued the company for three years of business expenses, claiming that they had falsely been labeled independent contractors and denied reimbursement.