The castle was rebuilt and extended to the south in the late 16th century. On 5 November 1620 a number of local and neighbouring landowners had dinner with Janet Lawson, Lady Fawside, at the castle and illegally combined together to set and raised the price of coals from their coalmines. The Privy Council of Scotland found their actions unlawful and the lairds were ordered to pay a fine of £2,000 and be imprisoned in Edinburgh Castle. In defence the landowners claimed their coal was unprofitable, that the workings of Little Fawside (belonging to the Master of Elphinstone) were on fire, and the Fawside coal mine had bankrupted the old laird.