It appears that you can sell your GERS' position now in TD Ameritrade but cannot purchase shares. Both Schwab and E*TRADE will allow both online buying and selling of GERS. There may be others and I would hope that if they are verified that they would be brought to public attention.
I think the problems buying at brokerage firms, just limits the bid. If you sell, you sell to the highest bidder. Or they buy from the lowest seller. The brokerage firm is just in between handeling your end. The one on the buyers side, handels his part. It can be the same firm, but it doesn’t need to be. Else, trading would even be harder. The bid and ask on trading sites all the same. Otherwise you would need to see lots of different bids and asks.
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