The Lock is the fifth of six paintings that make up the Stour series of large-scale rural works, that Constable exhibited at the Royal Academy between 1819 and 1825.
The painting is the only one of the series which remains in private hands, with the more famous The Hay Wain in the National Gallery, London.

After its exhibition in 1824, The Morning Post commented: "Mr Constable contributes a landscape composition which for depth, sparkling light, freshness and vigorous effect exceeds any of his works."
Samuel William Reynolds offered to make a mezzotint print, but never completed it.
His pupil  David Lucas eventually prepared one from Constable's private copy of the painting (Foster version).

On the opening day of the exhibition, James Morrison (1789–1857) an inn-keeper's son from Balham Hill, London, and Basildon Park, Berkshire, acquired the painting for 150 guineas, the only occasion in Constable's career when a painting sold on its first day of exhibition.
Its ownership then progressed down through his family:
Grandson, Colonel James Archibald Morrison (1873–1934), at Basildon Park
His daughter Mary, wife of Major John Dent-Brocklehurst of Sudeley Castle, Gloucestershire
The Trustees of the Walter Morrison Picture Settlement
On 14 November 1990 it was bought as lot No.128 for £10,780,000 at Sotheby's auction in London, by Baron Hans Heinrich Thyssen-Bornemisza and his wife Carmen "Tita" Thyssen.
This set a record for a British work of art, which it held until 2006 when a view of Venice by J. M. W. Turner, Constable's rival, sold for £20.5m at Christie's in New York.
From 1992, the couple placed the painting on loan to their museum, the Museo Thyssen-Bornemisza in Madrid, Spain.
It was part of the Baroness's personal collection rather than the main collection.

In light of "a lack of liquid funds", the Baroness decided in 2011 to sell the painting.
It was auctioned for  £22,441,250 at Christie's in London on 3 July 2012, following a low estimate of £20million, making it the joint fourth on the list of most-expensive Old Masters.
Museum trustee Sir Norman Rosenthal resigned in protest at the sale, saying that the decision to sell represented ".. a moral shame on the part of all those concerned, most especially on the part of Tita"
The Lock is the fifth of six paintings that make up the Stour series of large-scale rural works, that Constable exhibited at the Royal Academy between 1819 and 1825. The painting is the only one of the series which remains in private hands, with the more famous The Hay Wain in the National Gallery, London.
After its exhibition in 1824, The Morning Post commented: "Mr Constable contributes a landscape composition which for depth, sparkling light, freshness and vigorous effect exceeds any of his works." Samuel William Reynolds offered to make a mezzotint print, but never completed it. His pupil  David Lucas eventually prepared one from Constable's private copy of the painting (Foster version).
On the opening day of the exhibition, James Morrison (1789–1857) an inn-keeper's son from Balham Hill, London, and Basildon Park, Berkshire, acquired the painting for 150 guineas, the only occasion in Constable's career when a painting sold on its first day of exhibition. Its ownership then progressed down through his family:
Grandson, Colonel James Archibald Morrison (1873–1934), at Basildon Park
His daughter Mary, wife of Major John Dent-Brocklehurst of Sudeley Castle, Gloucestershire
The Trustees of the Walter Morrison Picture Settlement
On 14 November 1990 it was bought as lot No.128 for £10,780,000 at Sotheby's auction in London, by Baron Hans Heinrich Thyssen-Bornemisza and his wife Carmen "Tita" Thyssen. This set a record for a British work of art, which it held until 2006 when a view of Venice by J. M. W. Turner, Constable's rival, sold for £20.5m at Christie's in New York. From 1992, the couple placed the painting on loan to their museum, the Museo Thyssen-Bornemisza in Madrid, Spain. It was part of the Baroness's personal collection rather than the main collection.
In light of "a lack of liquid funds", the Baroness decided in 2011 to sell the painting. It was auctioned for  £22,441,250 at Christie's in London on 3 July 2012, following a low estimate of £20million, making it the joint fourth on the list of most-expensive Old Masters. Museum trustee Sir Norman Rosenthal resigned in protest at the sale, saying that the decision to sell represented ".. a moral shame on the part of all those concerned, most especially on the part of Tita"
The Lock (Constable)