FRANKFURT: Deutsche Bank's chief executive Christian Sewing will spend 15% of his monthly net salary buying the German lender's shares starting in September, a regulatory filing showed on Monday.

The filing makes official a pledge Sewing made in July, when he announced a major restructuring of the bank. Sewing said at the time he would invest a "substantial amount" of his fixed salary in the bank. The CEO, who is shaking up Deutsche Bank to try to revive its profitability, said in July he wanted to put his money where his mouth was.

Sewing will buy roughly 21,250 euros ($23,681.00) in shares around the 22nd of each month through to the end of 2022, the filing said. That would result in a total investment of around 850,000 euros, based on monthly purchases up to the end of 2022.

Deutsche Bank shares hit a record low of 5.78 euros per share on Aug. 16. At 1203 GMT on Monday, Deutsche's shares were at 6.64 euros each, up 1.1%. They are down 4.7% so far this year.

Last month, Deutsche Bank Chairman Paul Achleitner bought nearly 1 million euros of the bank's shares.