International students on F-1 visas who register full-time internships as Grad Co-op assignments are eligible for Curricular Practical Training (CPT) There is no limit to how much CPT may be worked as long as it is approved as an academic part of your degree. However, if you work more than 365 days of Full-Time CPT, you will forfeit 100% of your OPT available to you at your current degree level. Most students are not willing to give up the after graduation OPT, so students coordinate their CPT work amount with OIE so they do not exceed 365 days of FT CPT.
Part-time CPT is currently not counted toward that 365 day amount that leads to OPT forfeiture. Note, part-time CPT is available up to a maximum of 20 hours’ work per week.