California passed a law about that I believe. An excerpt from this [1]:
Section 2802 of the California Labor Code requires employers to reimburse employees for expenses “necessarily incurred” with the stated purpose of “prevent[ing] employers from passing their operating expenses on to their employees.” Lest anyone think this issue can be resolved with a waiver of the right to reimbursement, Labor Code section 2804 prohibits waivers of an employee’s rights to reimbursement.
it is unclear. I read an article yesterday saying California had just passed legislation to compensate for it. Obviously, it is pretty unethical, especially if you spend the majority of the day on the phone.
Edit 2: It was actually on Reddit. This is the link to Reddit commenting on the computer world article focusing on the same ruling at the appellate level: