Professors are usually appointed as civil servants (before and after tenure). These positions are compensated according to the salary scale for academia (“Wissenschaft”), the so-called “W-compensation” table. These salary scales differ depending on the federal state in which the employing university is located and the designation of the professorship: Junior or assistant professors are typically paid at the W1 salary level. Associate professors (fairly uncommon in Baden-Württemberg) are paid at the W2 level, while full professors are paid at the W3 level. These categories define base salary levels, which are frequently augmented by a bonus based on past performance (Leistungszulage).
Whether a professorship is designated as W1 or W3 is determined by university leadership, contingent upon approval by the state ministry, and is non-negotiable. The budget allocated to the professorship, equipment, and potential performance bonus payments are determined in the course of negotiations between the prospective appointee, the chancellor of the university, the dean, and the department.
A tenure track system has only fairly recently been introduced in Germany and does not work in the same way as in other countries. See the following overview of the different types of professorships available at the University of Tubingen for more information.