Green’s Dictionary of Slang

1. (UK Und.) a mock auction of cheap goods; also attrib.

1934		P. Allingham Cheapjack 72: The London Mob were working the R.O. This is short for the ‘Run Out.’ 320: R.O. (the run-out) – A fake auction.
1935		Thieves Slang ms list from District Police Training Centre, Ryton-on-Dunsmore, Warwicks 9: Run-out: Cheap jacking, Dutch auctioneering.
1938		(ref. to 1910s) F.D. Sharpe Sharpe of the Flying Squad 171: ‘Run out’ shops disposing of valueless jewellery worked in conjunction with the pickpockets. When the crowd outside these mock auctions got sufficiently thick out came the ‘hooks.’.

2. (UK Und., also run-out job) a jewellery shop robbery whereby a ‘customer’ requests a tray of jewels to be shown and then grabs them and runs out of the shop.

1955		B. Hill Boss of Britain’s Underworld 60: One of the most sensational run-out jobs we did was with a reporter attached to a well-known national daily newspaper.
1955		B. Hill Boss of Britain’s Underworld 60: ‘Please,’ he said, ‘please let me do a run-out.’ In the end we took him to a jeweller’s in islinton. It was a simple job. Bert grabbed the tray and ran.