Shares of WageWorks Inc. were up nearly 12% in Tuesday morning trading after health-savings-account company HealthEquity Inc. confirmed that it offered to buy WageWorks for $50.50 a share in cash. WageWorks shares recently changed hands at $48.35. "The proposed acquisition would accelerate HealthEquity's growth by creating the premier provider of both HSAs and additional consumer-directed benefits, including flexible spending and health reimbursement arrangements, COBRA and commuter accounts," the company said in a release. WageWorks confirmed that it had received the offer and said in its own release that it was working with advisors to review the proposal and "pursue the course of action that is in the best interests of all WageWorks shareholders." HealthEquity's stock is down 6.6% in morning trading. It has gained 16% so far this year, as the S&P 500 has risen 17%.