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  5. CSU: Yesterday (Dec 10) I submitted the following question [Constellation Software Inc.]

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Q: Yesterday (Dec 10) I submitted the following question:

“I had an order in today to buy 3 CSU shares at $3251.00. I noticed that at least 4 times today the stock fell below that price. The low for the day was $3250.00. My order was not filled despite being above the low for the day on at least 4 occasions. Can you explain why my order was not filled? If the reason is because I am buying only 3 shares, then how do I buy such a small amount if my order is being ignored? I am reluctant to place a market order when the trading volume is relatively low.”

You asked what time the order was placed. It was Dec 10th at 10:24:43 am ET using RBC Direct Investing.

After the market closed yesterday I did call RBC DI to get an explanation. The person gave a few answers that just didn’t make sense, and said it was the first time he had a call with a question like mine. He tried to deny that there were any trades below $3252.00 and that’s why my order was not filled, then finally admitted he saw a trade for 4 shares below my bid price, and would have to investigate further.

Today (Dec 11), I placed another day order to buy 3 CSU shares at $3250.50. The same thing was happening this morning. The price was trading below my buy price and still my order was not getting filled. I called RBC DI and spoke to a licensed trader who gave me this explanation. An order for 3 shares is an odd lot, and odd lots go to a different exchange, and it depends on the shares available for sale on that exchange. She also said a lot (100 shares) gets priority (which I thought was not an issue anymore).

Does that explanation make sense to you?

Maybe others who have placed odd lot orders have experienced this problem.

p.s. By the way, while I was on hold at RBC DI, my order got filled at a lower price than my bid price. She told me my order went to the CBOE exchange.
Asked by Paul on December 11, 2025
5i Research Answer:
Yes the odd lot explanation makes sense, they are not guaranteed on price execution. We...
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