The three casts are on public display on College Green in Westminster, London; Queen Elizabeth Park in Vancouver; and the garden at Kykuit, the house of the Rockefeller family in Tarrytown, New York.

The Westminster cast was donated by Moore through the Contemporary Art Society to what he believed was the City of London, but its actual ownership was undetermined for many years.

The Westminster cast subsequently fell into disrepair, and was restored in 2013 after it became part of the British Parliamentary Art Collection; it was granted a Grade II* listing in January 2016.

[14] Moore made a larger and reversed version of the sculpture, Mirror Knife Edge 1977 or Knife Edge Mirror Two Piece (LH 714) – which is 5.34x7.21x3.63m or about 17.5x23.7x11.9 feet and weighs about 15 short tons (14 t) – which was commissioned for the entrance to I. M. Pei's east wing of the National Gallery of Art in Washington, D.C.[15] The work is carefully cleaned and conserved each year to maintain the distinction between its shiny and patinated surfaces, as the artist intended.

[16][17] The second cast of Knife Edge Two Piece is located in Abingdon Street Gardens, also known as College Green, opposite the Palace of Westminster in London.

[9] He welcomed the fact that the sculpture would be next to a public path and would have seating nearby to allow contemplation, and compared the gardens favourably with the setting for Hubert Le Sueur’s equestrian statue of Charles I at Charing Cross, "which, in order to look at closely and appreciate in detail, you have to risk your life in crossing a maze of traffic".

[9] The siting of the sculpture was disliked by some, with Neil Marten MP asking Parliament why "this lovely part of Westminster should be littered with something that looks like a crashed unidentified flying object.

[19] The land where it is situated was a bombsite in the Second World War, and is owned by the Parliamentary Estate; Westminster City Council operates a car park underneath.

[9] Though it is worth an estimated £5m, no conservation work ever took place on the sculpture, and its ownership was unresolved until the House of Commons agreed to take responsibility for it.

[18] Due to a lack of maintenance, the protective lacquer covering Knife Edge Two Piece degraded and exposed the surface of the sculpture to the elements.