The symbol “Q”, currently as “Qnity Electronics”, was listed on S&P 500 as of 3 Nov 2025. Its historical stock bars were then accessible via Alpaca’s API.
However, the symbol “Q” was also used to denote the company “Quintiles IMS” back in 2016 and 2017.
Alpaca likely keys stock identity via the ticker/symbol. As a result, the stock prices of these two companies are combined under the same symbol “Q”, which is incorrect.
The attached screenshot shows the close prices of historical bars retrieved from the symbol “Q”. It can be seen that there is a large gap between the two time-series data, with (1) preexisting stock prices of previous symbol “Q” in 2016 and 2016, and (2) the Qnity Electronics data being available after 3 Nov 2025.
Thank you for reporting this issue. Alpaca does indeed uses the stock symbol as the identifier for market data, for example for historical bars. However, we provide an option to map these symbols to their actual companies and follow their name changes using the asof parameter of the historical endpoints. By default, this mapping is enabled.
Unfortunately, it isn’t always perfect. In this case we were missing the new “Q” (“Qnity Electronics Inc.”) entry and this caused the issue you described.
The issue now has been fixed. If you now query the endpoint
with the default asof, you’ll only see the bars of “Qnity Electronics” starting in 2025
with asof < 2017-11-15, you’ll get the bars for the old company, which since 2017-11-15 has been using the ticker symbol “IQV”.
