Otto A. Malm was a modern businessman in many respects. He extended the activities of the merchant firm to comprise industry, communications and investment. He operated on the stock exchanges of Stockholm and London and owned shares e.g. in the Central Bank of Australia. On his initiative and funded by him a railway track was built to Jakobstad. Malm was also engaged in the service of society: he was the first chairman of the City Council of Jakobstad and an Auditor of the Bank of Finland.
In his will, Otto A. Malm deposited two million marks as a trust "for promoting higher teaching, general education, institutions serving the common good, and for research". In 1932 the trust was registered as a foundation. Malm also supported other social establishments. He donated the means for building and running a hospital in Jakobstad, known as the Malm Hospital, as well as money for the beautification of the town. Still, his primary wish was to support purposes "that may benefit our Fatherland as a whole".