In the context of the input sentence, determine the relationship between 'Brian Hartzer' and 'Westpac'.
Options: product/material produced, owner of, distributed by, employer

There have been some excellent recent examples of this including the following appointments: Brian Hartzer at Westpac Banking Corp, Jon Sutton at Bank of Queensland, Ryan Stokes at Seven Group Holdings, Peter Tonagh at News Corp Australia and Chris Smith at CSL.
employer