(Sharecast News) - Polar Capital co-founder Brian Ashford-Russell disposed of 250,000 ordinary shares in the AIM-listed investment manager on Thursday, lowering his stake to a total of 5.52% of the company's issued share capital in the process.Ashford-Russell, who helped set up the firm back in 1996, sold the shares at an average price of 485p, for a total value of £1,212,499.98.Back in December, analysts at Peel Hunt named Polar Capital as one of 29 companies it believes will double in value in the next two to three years.In its "Stock Ideas for 2019: Doublers" note, Peel Hunt conceded that although it was difficult to predict how Brexit would affect markets, it added that there was "always some stocks that are dancing to their own particular tune which could deliver some healthy returns."As of 1640 GMT, Polar Capital shares had slipped 3.69% to 470p.Top Director BuysF&c Investment Trust (FCIT)Director name: Bone,RogerAmount purchased: 150 @ 663.77pValue: £995.66F&c Investment Trust (FCIT)Director name: Hewitt,JeffreyAmount purchased: 75 @ 663.77pValue: £497.83F&c Investment Trust (FCIT)Director name: Knapp,EdwardAmount purchased: 15 @ 663.77pValue: £99.57Top Director SellsPolar Capital Holdings (POLR)Director name: Ashford-Russell,Brian J DAmount sold: 250,000 @ 485.00pValue: £1,212,499.98