Institutional Investors Increase Stake in AngioDynamics Institutional investors, including Principal Financial Group and Rhumbline Advisers, have significantly increased their holdings in AngioDynamics, Inc. during the fourth quarter. Principal Financial acquired 95,961 shares, valued at $879,000, while Rhumbline Advisers added to their stake, now holding shares worth $554,000. The company’s stock has seen a steady rise in recent months.12