The largest insider transaction on today's list is a Form 4 filing by ValueAct Partners.

ValueAct reported a purchase of roughly $10 million in Insight Enterprises $NSIT.

Ernest S. Rady, the chairman and CEO of American Assets Trust $AAT, continues to appear on our list with his eighth Form 4 filing in the trailing month.

Rady reported his latest purchase on Friday, revealing another 25,000 shares, equivalent to $719,600.

The largest insider transaction on today's list is a Form 4 filing by Cevian Capital.

Cevian reported an $11.4 million purchase in Autoliv $ALV, the world’s biggest manufacturer of airbags and seatbelts for cars.

Jim DeFranco, the executive vice-president of Dish Network $DISH, is on our list again today with his fifth Form 4 filing in August alone.

DeFranco, who co-founded the broadcasting company over 40 years ago, disclosed a purchase of $2.5 million in his latest filing.

The largest insider transaction on today's list is a Form 4 filing by H Partners Management, which reported an $11.6 million purchase in the theme park Six Flags $SIX.

The hedge fund has a total stake of 11.50% as well as a seat on the board.

The largest insider splash on today’s list is a Form 4 filing by Gregory Bailey, an independent director at Biohaven Pharmaceutical $BHVN.

Bailey reported the purchase of approximately $5.6 million in his company’s stock.

The largest insider buy on today's list is a Form 4 filing by Bill Gates, who revealed an additional purchase in Ecolab $ECL worth $19 million.

This is the third Form 4 filed by Gates in the last five days, as he continues to add to his position.

The 13D that has everyone’s attention today is not going to be on our list. That’s because we’re looking for insider buying, not insider selling.

Which brings us to meme stock master and Gamestop $GME Chairman Ryan Cohen.

The largest insider buy on today’s list is a Form 4 filing by Bill Gates.

Gates revealed an additional purchase worth $25 million in Ecolab $ECL, as he continues to add to his position.

The most significant insider transaction on today’s list comes in a 13D from Carl Icahn.

Icahn increased his ownership stake in the natural gas services company Southwest Gas Holdings $SWX from 7.6% to 8.7%.

Elliott Management is at it again.

Following the revelation of large stakes in Paypal $PYPL and Pinterest $PINS just last month, the activist fund was in the news again on Monday.

This time it’s targeting the healthcare space, with a large investment in Cardinal Health $CAH.

The most significant insider activity on today’s list comes in a Form 4 filing by QH Hungary Holdings Ltd, which reported purchases worth roughly $9.2 million in Quaker Chemical $KWR.

The firm now owns 4,440,989 shares, representing a roughly 22.50% ownership stake.