Aggregating MRDs from 403(b) Plans

[DTH]

Can an individual calculate the MRD from each 403(b) contracts they have and have it paid from one or more contract even if the individual has contracts with different employers?

The regs (1.403(b)-6(e)) state that "...only amounts in section 403(b) contracts that an individual holds as an employee may be aggregated..."

This leads me to believe the aggregation rules only apply to multiple 403(b) contract held under one employer. If the employee has a contract with a school plan and a contract with a hospital plan, the indivudual would need to get two MRDs, one from each plan.