Rules just issued by the Treasury Department give a one-year extension to the health insurance mandate for mid-sized businesses. Companies with 50 to 99 employees will now have until January 1, 2016, to provide health insurance for employees or face penalties. Employers must certify that they have not cut workers in order to come under the 100 employee threshold. Companies with 100 or more employees must still meet the January 1, 2015, deadline for providing health insurance coverage.