The Vanguard Group has invested $9.2m more in Seacor Holdings, marking the third investor move in the diversified owner in the past week.

Vanguard has purchased 204,498 units of the Charles Fabrikant-led company, upping its interest to 9.3% from 8.4% held a year ago. It now owns 1.7 million Seacor shares.

BlackRock and BlackRock Fund Advisors together own nearly 25% of the company's 18.25 million outstanding units, which gained 1.4% to $44.83 by mid-morning.

Wellington Management let go of 195,549 Seacor shares while BlackRock picked up another 368,000, according to SEC documents filed over the past few days.

Dimensional Fund Advisors cut its position in Seacor Holdings by 6,200 shares to 1.5 million.