All three points you raise are important.

The fact that GDXJ bought the 10 mln shares of ECU just a week before the merger indicates the merger has been a confidential affair. Congratulations to ECU and AUMN for that . I don't think Van Eck will have regulations forcing them to get rid of the ECU shares before the shareholders of both companies have voted on the proposed merger in two weeks time. After the vote there is no reason to change anything either, whatever the decision. The New Gold Minerals should fit perfectly into the GDXJ profile as well. As you say, the Fund may add shares of the new AUM due to the doubling of its market capitalization.