On Friday, Pennsylvania-based Conestoga Capital Advisors disclosed selling 855,435 shares of Vertex (VERX +0.43%), an estimated $24.8 million transaction based on average prices in the third quarter.What HappenedAccording to an SEC filing released Friday, Conestoga Capital Advisors reduced its position in Vertex by 855,435 shares during the quarter ended September 30. The estimated value of the shares sold was approximately $24.8 million, calculated using the average closing price from July 1 to September 3 ...