Option trading volume inconsistencies

Question

May I ask for your opinion on option trading volume numbers?

A recent example might be DNN (Denison), a call option,expiration Mar 19, strike $2.50

Yahoo says in the option chart that the volumes were 85m Feb11, and 64m Feb16 (yesterday).

On Barchart Premium I found volumes 338k for Feb11 and 206k for Feb16, which seems reasonable.

When looking at Robinhood option data (10minute interval or similar), there are prices but the volumes are all just zeros. I have no other data sources.

Does it mean that Yahoo's option historical volume data is a nonsense, a bug or it means something?
I assume Robinhood has the data but might not want to publish too much (Citadel activities???)

I also noticed tha t the sum of Robinhood stock intraday volume data is much less than a total daily volume on Yahoo/Barchart. So not sure about Robinhood data in general.

But Barchart also says that the same option (DNN210319C00002500) for
Feb10 is 6k volume and 2k open interest.
Feb11 is 338k volume and 7k open interest.
Feb12 is 144k volume and 149k open interest.

Does it mean that Feb11 only 5k new contracts were opened but they changed hands many many times? And Feb12 almost all actions were new contracts with almost no trades?
Or am i wrong? Or incorrect data?

Thank you

Answer 1

Regarding disparities in daily trading volume, all I can say is that Yahoo Finance is known for bad data and that Robinhood is a Mickey Mouse operation. Is that the case here? I don't know. If you want to check on the accuracy of option trading volume, do it in real time and compare brokerage firm numbers not secondary web site data providers. CBOE and NASDAQ data is reliable if you can find it.

But Barchart also says that the same option (DNN210319C00002500) for: Feb10 is 6k volume and 2k open interest. Feb11 is 338k volume and 7k open interest. Feb12 is 144k volume and 149k open interest.

Does it mean that Feb11 only 5k new contracts were opened but they changed hands many many times? And Feb12 almost all actions were new contracts with almost no trades?

Open interest is a lagging number. It is not updated throughout the day. At night, the OCC tallies up the day's trades and posts the open interest the next morning. This is borne out by your data where there's a 332k spike in contact volume on Feb 11th and a 142k spike in the open interest on Feb 12th.