Cry me a river, snowflake.
"Once each player has had the opportunity to buy shares play progresses to the auction of the next company’s available shares, i.e. a player never has a second opportunity to buy shares in a single game turn."
It should read "a player never has a second opportunity to buy shares of any one company in a single game turn."
At least that's how we played. I never noticed that sentence but only 5 opportunities to buy shares in the entire game wouldn't make any sense.