ETF symbols with Reorg Events generate ERROR Messages

Certain ETFs have had "Reorg Events" in which their names and ownership have changed, but in which the underlying ETF has not changed. From a portfolio manager's perspective these Reorg Events are Non-Events. However, these ETFs generate ERROR Messages when initialized without special treatment, even though there has been no meaningful change in the underlying ETFs.

I would like to be able to trade these symbols on BOTH sides of the Reorg Event, continuously, as though the Reorg Event had not happened.

Symbols with this problem include SMH, OIH, EEM, VNM, and HYG.

The best fix would be in the Quantopian database, to correct the Reorg Event and allow for continuous trading. Absent this, I would like to know if there is a work around I can program into my algorithm.

If someone would please post the sample code that will permit me to do this I would be very grateful. Thank you!

Here are sample ERROR Messages:

175 Error There are multiple assets that have used the symbol SMH. You must use set_symbol_lookup_date() before using symbol(). The table below shows when each company traded using the symbol SMH. Learn More
ASSET FIRST TRADED LAST TRADED
SEMICONDUCTOR HOLDRS TRUST 2000-05-04 2011-12-19
MARKET VECTORS SEMICONDUCTOR E 2011-12-20 2015-11-08

There are multiple assets that have used the symbol EEM. You must use set_symbol_lookup_date() before using symbol(). The table below shows when each company traded using the symbol EEM. Learn More
ASSET FIRST TRADED LAST TRADED
MERRILL LYN & CO 1997-11-16 2002-12-04
ISHARES MSCI EMERGING MARKETS 2003-04-10 2015-11-05

If you buy and hold the ETF before the event, what happens to it? Does it correctly convert to the new ETF? Or does it simply stay in your portfolio and get no price/volume updates? I ran a simple backtest, attached, and it appears to not get updates.

In general, we rely on our data provider to tell us about corporate events like mergers, dividends, splits, etc. I'm not immediately familiar with this particular corporate event type. I'll write a bug and work back through our vendor to figure out how to get this type of event handled better. That takes some time, though.

I think that as a workaround, you need to use a pre-set list and buy and sell on key dates so you manually exit the old position and come into the new position. That, of course, does introduce some look-ahead bias, but if you just use the list to maintain a position that you otherwise honestly are choosing to make, it should be OK.

In real money trading, this won't be an issue presumably because the broker will do the switch under the covers, and Quantopian simply syncs in the broker's positions.