Finding Delisting and Symbol-Change Data for Illiquid Stocks
Summary
The discussion explains why tracking inactive or rarely traded stocks requires more than observing daily prices. A stock may stop trading on its main exchange, move to an over-the-counter market, change symbols, merge, or enter bankruptcy proceedings, and data vendors can represent these events differently. Some may report a zero price, while others use event codes or omit the event from ordinary price records.
The responses recommend high-quality historical data for standardized corporate-action and delisting information, while warning that comprehensive coverage is unlikely to be freely available in a convenient download. They also point to a Nasdaq symbol-change listing as a possible research aid, but note its coverage may be incomplete and the information may require manual extraction. The guidance is especially relevant to illiquid securities and survivorship-aware research; it does not identify a complete free source or provide a specific data-cleaning workflow.
Key ideas
- Sparse price updates alone do not reliably reveal whether a security has stopped trading.
- Vendors may encode bankruptcy, mergers, symbol changes, or delistings in different ways.
- High-quality historical datasets can provide standardized event information, usually at a cost.
- A public symbol-change listing may help, but its coverage and download options can be limited.
Tags
Full text
# Where can you find data on non-trading stocks?
# Where can you find data on non-trading stocks?
My data source for end of day prices only gives the prices of the trades during the day. If a stock stops trading/goes out/moves to another exchange|changes symbol. I never hear about this.
My question(s) are:
- Is there a way to determine that a stock is no longer trading? Most stocks that I have, have daily updates to the price. Some stocks only have price listings once a month or once every blue moon.
- Is there a data source [preferably free, without parsing through news stories] that I can grab that can give updates on symbol changes/delistings/going to 0.0.
## Answer by strimp099 (score 3)
https://quant.stackexchange.com/a/2159
It really depends on what you are trying to do with the data. It sounds like you are dealing in very illiquid stocks trading OTC or on the pink sheets, etc and if they only trade ("have price listings") "once every blue moon", you probably have a lot of manual intervention and research to do in building your data series.
With that said...
- It depends on the data source. If an issuer goes bankrupt, sometimes their shares move to the pink sheets to facilitate class action lawsuits, bankruptcy proceedings, etc. Further it depends on the how the data vendor treats such events. Some might sources show the price as $0, some might have a code for what has happened (bankruptcy, merger, change of symbol, etc.).
- Chicago Booth's Center for Research in Securities Prices (http://www.crsp.com/) has very high quality historic data which contains the information you are looking for, albeit not for free. The type of data you are looking for would only come from a fairly high quality source. In my opinion you would be very hard pressed to find it standardized and delivered on a silver platter (or CSV file) for free.
## Answer by joshayers (score 3)
https://quant.stackexchange.com/a/2160
NASDAQ's website has a list of symbol changes.
http://www.nasdaq.com/markets/stocks/symbol-change-history.aspx
Looking through a few of the listings, there are some Pink Sheet companies included, but I can't say if it's comprehensive.
Unfortunately, it doesn't seem like that have the data in an easily downloaded format. You're probably stuck parsing it from the webpage.Shown in full with attribution under the source's licence. Licence: CC BY-SA 4.0 (Stack Exchange)
This summary was written by Stratmill's research agent from the original; it is not a copy of the source.