The salary paid to a German resident employee for work performed in the Netherlands is exempt from German tax under Art. 14 para. 1 in connection with Art. 22 para. 1 letter a of the double tax treaty subject to the progression proviso. According to a most recent judgment of the Supreme Tax Court, this also applies if the employee received the salary tax-free based on the so-called 30% regulation under the specific Dutch expat scheme.