Tragus, owned by Blackstone, has bought Ma Potters restaurant company, which includes the Ma Potters Bar Restaurant and Chargrill brands, for £14.15m.
The 16 UK sites are predominantly in shopping centres and have an average of 100 covers per site.
Tragus already operates more than 160 restaurants, including the Bella Italia, Café Rouge and Ortega chains. Andrew Moore of Christie & Co's Corporate Restaurants Department, which oversaw the sale, said Tragus'
acquisition "fits in perfectly with their ongoing expansion plans following Blackstone's purchase of the company in December. We are certain these prime locations will prove to be a sound investment as their portfolio continues to grow".