By 1879, together with his brother August, who replaced the departing general Christian, the previous authorized representative Wilhelm von Finck already held a large part of the bank assets.

The bank was involved in the founding of companies such as the Süddeutsche Bodencreditbank AG (1871), the brewery Bürgerliches Brauhaus München (1880), the Isarwerke GmbH (1894) and the Münchener Trambahn-AG.

As a representative of the bank, Wilhelm Finck often took on a supervisory board mandate with the shareholdings and thus brought his economic expertise to a wide variety of companies.

After the bank had developed positively in the deposit, lending and securities business at the turn of the century, the First World War interrupted the upswing.

Merck Finck & Co. made a major contribution to the founding of aircraft construction and air traffic companies: with Udet-Flugzeugbau GmbH, a predecessor of today's DASA, and Süddeutsche Aero Lloyd AG, a predecessor to Lufthansa, important industry pioneers were created in Germany.

[2] Due to its owner's (August von Finck Sr.) close ties to Nazi regime, the bank took part in numerous hostile overtaking of Jewish owned companies all across Germany and annexed Austria.

de:J. Dreyfus & Co. was one of many privately held companies forced to be sold to Hitler's entrepreneurs in the process of Aryanization.

After the annexation of Austria to the German Reich in 1938, Merck, Finck & Co. took the opportunity to acquire Wiener Privatbankhaus S. M. v. Rothschild.

This highly renowned Austrian private bank, owned by Louis Nathaniel de Rothschild, had controlled the Österreichische Kreditanstalt until 1931.

Merck Finck & Co. took over the business of the banking house Alwin Steffan from Frankfurt am Main, to which it had longstanding connections, with the death of the senior partner in 1963.

On 21 May 2010, the Indian investment company Hinduja Group announced that it would take over the KBL European Private Bankers division from the Belgian KBC Bank for €1.35 billion.

In December 2020, Merck Finck Privatbankiers AG was integrated into the parent company, the European Quintet Private Bank (Europe) S.A.

The main focus of business activity is the consulting and management of large assets with a private or entrepreneurial background.

The Quintet group owns private banks in Belgium, Denmark, Germany, United Kingdom, the Netherlands and the Grand Duchy of Luxembourg.