Knabrostræde 30, also known as Det Ferske Fiskehandler-Kompagnis Hus (The Fresh Fish-Trading Company's House), is an 18th-century former fish warehouse situated on the Gammel Strand-Nybrogade canalfront, opposite Thorvaldsens Museum, in central Copenhagen, Denmark.

[5] Their daughter Dorothea Ludwigsen (1779-) married the bookkeeper and later bank manager Gunni Olsen Busck (1765-1821).

[6] The other tenants were a royal kitchen clerk (kongelig køkkenskriver), an accountant in Rentekammeret (renteskriver) and a beer vendor (øltapper).

[2] Ludvigsen's daughter Birgitte and her husband Peder Horrebow Homann (1683—1861) were by 1840 residing with their three children on the ground floor.

[10] The illustrator Peter Christian Nygaard Mattat Klæstrup resided on the first floor at Knabrostræde 30 in the years around 1864.

Carl Bang, a combined fish wholesale and retail business, was in the last part of the century based in the basement.

[11] The building was in more recent times acquired by Bent Fabricius-Bjerre and his two sons via the property companyb Metorion.

In January 2021, it was announced that Vision Ejendomme/Vision Properties had acquired Knabrostræde 30as part of a portfolio of eight historic buildings.

[12] The building is constructed in red brick with three storeys over a walk-out basement around an asymmetrically shaped light well.

The facade towards Knabrostræde is crowned by a three-bay gabled wall dormer with a pulley beam.

The main entrance in one of the two central bays is surrounded by a lavishly decorated sandstone portal, incorporating a round window with the house number (30).