RE: I bought a few stocks in the early 90’s. I’ve never heard of the round lot and those were not round lots or close.
A larger player only had to make a fraction of a percent to pay for his commission. This is why the institutions and big investors ruled the markets and the little guy was shut out. This “hurdle” made the individual investor stay in a trade longer just to get to profit territory. So he traded less often.
He was also priced out of buying stocks such as Amazon or Nvidia which have stock prices of over $3,000 and over $700 per share.
A round lot of Nvidia would be $70,000 just for that one position! Most individuals don’t have that kind of money to trade in a single stock if they’re trying to be diversified into 10-25 stock.
But Now, we have “fractional share” ownership. Anyone can buy just a slice of Amazon with as little as $50. This fractional ownership, which only just came onto the scene in the last few years, has solved the round lot problem and made it a term we may never hear about again.
I was only addressing a particular claim and my personal experience is that though this may have been a thing at some time, it wasn’t in the early 90’s when I bought a couple of stocks.