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2009-11-13: I'm trying this today because I want to see if I can loan out my stock that we're holding long term.
It takes a couple of days setting up. I've upgraded my account to Portfolio Margin, which is meant to lower the margin required by considering related positions.
Next task I had to do is request trading access separately.
2009-11-17: After getting trading access, it seems I cannot loan out my stock. The shares must be held by DTC, but my shares are held by IB.
2011-02-08: it seems that I can loan out now, but I still don't really understand the interest rates so I haven't bothered. Besides with interest rates so low it is probably not worth the effort.
2011-02-08: Interactive Brokers now offer CFDs for UK stocks.
2011-07-09: Instead of AQS, you can now let IB manage the lending out of your stock with a 50% commission. I won't look into this as interest rates are still close to 0. I wonder if they will lend out non-US stock. They call this the Stock Yield Enhancement Program.
EUR.ILS and USD.ILS were added, I will check if they can be traded and new positions can be opened.