On 27 October 2008, Porterbrook was purchased from Abbey National by a consortium of Antin Infrastructure Partners, Deutsche Bank and Lloyds TSB.

[6] On 28 August 1996, the company was purchased by the transport conglomerate Stagecoach in exchange for £825 million; this deal was subject to considerable criticism for the low value returned to the taxpayer.

[13][14][15] On 27 October 2008, the business was purchased from Abbey National by a consortium of Antin Infrastructure Partners, Deutsche Bank and Lloyds TSB.

[16][17] The sale, which reportedly valued Porterbrook and its 6,014-strong rolling stock inventory at £2 billion, gave rise to concerns that Abbey National, and its Spanish parent Banco Santander, were subject to considerable financial stress at that time.

[21][22][23] During the 2010s, Porterbrook begun disposing of their Class 43 power cars, used on Intercity 125 services; a number of power cars (along with a set of Mark 3 coaches) were acquired by Locomotive Services Limited,[24] while the two locomotives involved in the record breaking test run were donated, one, 43102, to the national collection at Shildon, and the other, 43159, to the 125 Group.

[28] In February 2020, Porterbrook signed a 15-year lease with St Modwen to take over the Quinton Rail Technology Centre at Long Marston.

[29][30] In 2020, it was announced that Porterbrook was funding a £55 million five-year Project Aurora programme to refurbish 214 Class 377 'Electrostar' EMUs operated by Southern Trains.