Or. Rev. Stat. § 659A.275

      659A.275 Undue hardship. (1) As used in this section, “undue hardship” means a significant difficulty and expense to a covered employer’s business and includes consideration of the size of the employer’s business and the employer’s critical need for the eligible employee.

      (2) A covered employer may limit the amount of leave an eligible employee takes under ORS 659A.272 if the employee’s leave creates an undue hardship on the employer’s business. [2007 c.180 §4]