In 1790 the estate was bought by timber merchant and shipowner Bernt Anker (1746–1805), Norway's richest person at the time. He extended the main building to its present size. There he would reside with his wife, Mathia, until he died a childless widower in 1805. Frogner was bought by his nephew Morten Anker in 1807. His business was hard hit by the economic depression during and after the Napoleonic wars, and he eventually went bankrupt and was forced to sell Frogner by auction in 1836. The buyer was the director-general of the Modum Blue Colour Works, Benjamin Wegner, who was married to Henriette Seyler of the Hamburg Berenberg banking dynasty.