context: Ersatzschulen are ordinary primary or secondary schools, which are run by private individuals, private organizations or religious groups. These schools offer the same types of diplomas as public schools. Ersatzschulen lack the freedom to operate completely outside of government regulation. Teachers at Ersatzschulen must have at least the same education and at least the same wages as teachers at public schools, an Ersatzschule must have at least the same academic standards as a public school and Article 7, Paragraph 4 of the Grundgesetz, also forbids segregation of pupils according to the means of their parents (the so-called Sonderungsverbot). Therefore, most Ersatzschulen have very low tuition fees and/or offer scholarships, compared to most other Western European countries. However, it is not possible to finance these schools with such low tuition fees, which is why all German Ersatzschulen are additionally financed with public funds. The percentages of public money could reach 100% of the personnel expenditures. Nevertheless, Private Schools became insolvent in the past in Germany.
question: What, in relation to regulations involving those who are paid to share their knowledge, makes private schools similar those controlled by the leaders of the German state?