For guidance on what may cause a 403(b) plan to be subject to ERISA, please consult the Department of Labor's rules. With the publication of Revenue Ruling 202023, the IRS completed a cycle of helpful guidance regarding the termination of 403(b) plans.Participation Guidelines. Necessary to fund the Retirement Plan in accordance with the requirements of ERISA. An employer with a 403(b) plan subject to ERISA should ensure that the Summary Plan. Set aside money towards their retirement. All 403(b) plans are subject to Title I of ERISA unless an exemption applies. This article discusses preapproved Internal Revenue Code (I. Regular full- and part-time employees who work at least 1000 hours per year are eligible to participate in the Section 403(b) retirement program administe. Most employersponsored retirement plans are subject to ERISA requirements.