It has nothing to do with commissions. You pay the MM a fee
I can hear it now, some poor MM getting flooded with calls from retail wanted to "save a bundle" too. LOL
You might want to expand, and explain an insider wanting to dump millions of shares, they awarded themselves at a cost of $0.00 in a given range dpesn't quite work the same as fur a retail trader. The MM will be charging a fee well beyond what a retail trader pays to a discount broker, for a few trades. But for the insider it's far cheaper, than to be dinged by a discount commission, for possibly hundreds of trades.
Maybe I should substitute Agency Trader instead of MM per Integral's recent post.
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