When Watt's business partner, John Roebuck was unable to pay a debt to Boulton, he accepted Roebuck's share of Watt's patent as settlement. He then successfully lobbied Parliament to extend Watt's patent for an additional 17 years. This enabled the firm to market Watt's steam engine. The firm installed hundreds of Boulton & Watt steam engines in Britain and abroad, initially in mines and then in factories.