So, there's a big store called Costco that sells lots of things in bulk. The boss of the store, Craig Jelinek, sold some of his shares in the company, which means he doesn't own as much of it anymore. He made about $5.49 million from selling them. This could mean he thinks the store isn't doing very well or that the price is too high.

Another company called THOR Industries makes big cars called motor homes. The person in charge, Todd Woelfer, also sold some of his shares and made around $774,923. This might mean he thinks the company isn't doing very well either or that the price is too high. Read from source...

- The title is misleading, as it implies that insiders are selling in bulk or en masse, while the article only mentions four sales transactions.
- The article does not provide any context or analysis on why these specific insiders decided to sell their shares, nor does it compare them with other insider buying or selling activities in the same sector or market cap range.
- The article relies on a vague and outdated definition of insider sales as "a preplanned sale" or "indicating concern in the company's prospects" without acknowledging that there could be other motivations, such as tax planning, diversification, estate planning, etc.