US turnaround investment firm Sherborne Investors continues to sell shares in Spirent Communications, the UK telecoms testing equipment maker it bought into three years ago. Sherborne, which took a 15% interest in August 2006, has just sold 7.5m shares at 79.34p each, cutting its stake to 52.7m, or 7.83% of the business.That disposal, plus the decision to offload 10% of the company, or 70m shares, at 78.78p early last month, have netted Sherborne about £59m.It had wanted to get rid of 75m shares exactly a year ago, but institutions were unimpressed with the price, so the sale was scrapped. A subsequent slump in the share price, which fell more than 50% over the next four months, forced Sherborne to keep the stock until conditions improved.The Americans took control of Spirent in December 2006 when they ousted chairman John Weston and two non-executive directors in a boardroom coup. Edward Bramson, a managing member of Sherborne, became executive chairman of Spirent, and then non-executive chairman from September 2008.Another partner in Sherborne, Gerard Eastman, became a non-executive director of Spirent.Last month, Spirent said it has maintained profitability in 'difficult market conditions'.Pre-tax profit rose 1% to £23.6m on revenue up 15% to £139.1m as a result of currency benefit. Revenue fell 10% without currency gains."We remain optimistic that in the second half of 2009 our diversified solutions portfolio will allow us to continue to increase market share," said the group.