California's Supreme Court is set to clarify the state's rules for determining when employers must provide workers with a place to sit.

The court's opinion, expected Monday, stems from lawsuits brought by cashiers at the CVS drugstore chain and tellers at Chase Bank who said they were wrongly not provided with seats while working. The companies face millions of dollars in potential penalties depending on the California Supreme Court's interpretation of the rules. The court's opinion would affect other similar cases in the state.

Employers in California must provide employees with "suitable seats" when the nature of the employees' work reasonably permits the use of seats.

The CVS and Chase Bank lawsuits are now before the 9th U.S. Circuit Court of Appeals. That court asked the California Supreme Court to determine whether each task employees perform must be evaluated to determine whether it qualifies for a seat. The 9th Circuit also asked whether the employer's judgment about whether the employee should stand and the physical layout of the workplace must be taken into consideration.

CVS and Chase Bank say the seat rules require a holistic approach that determines the nature of employees' work by considering the entire range of tasks they perform, according to the 9th Circuit.

In CVS' case, cashiers also stock shelves and perform other tasks that require them to stand. The companies also say the employees' job descriptions, the layout of the workplace and the business' judgment about whether employees should stand must be considered, according to the 9th Circuit.