• Insider buying can be an encouraging signal for potential investors, especially when markets are near all-time highs.

• A leading asset manager and a special purpose acquisition companies attracted some notable insider buying last week.

• Beneficial owners were in the spotlight as earnings season means buy windows are close for many insiders.

• Conventional wisdom says that insiders and 10% owners really only buy shares of a company for one reason -- they believe the stock price will rise and they want to profit from it. So insider buying can be an encouraging signal for potential investors, particularly when there is uncertainty in the markets or the markets are near all-time highs.

Note that a new earnings-reporting season is ramping up, and many insiders are prohibited from buying or selling shares. Here are a few of the most noteworthy insider purchases that were reported in the past week.

Acutus Medical

Early last week, two Acutus Medical Inc (NASDAQ: AFIB) directors took advantage of a public offering of common stock priced at $14 a share. The more than 2.14 million shares they indirectly purchased altogether totaled nearly $30.0 million. As one director has a stake of over 3.4 million shares and the other's stake is more than 4.87 million, each is a beneficial owner as well.

Kerrisdale Advisers recently reported in a 13G filing a 5.25% stake in the medical devices maker, and the share price was at $16.70 as Friday's regular trading ended. That was up almost 24% in the past week. The stock has traded as high as $38.99 in the past 52-weeks, but it has just a $20.00 consensus price target.

Fast Acquisition

Special purpose acquisition company (SPAC) Fast Acquisition Corp (NYSE: FST) saw a beneficial owner return to the buy window last week. At $11.30 to $12.19 per share, the 532,000 shares most recently acquired totaled more than $6.20 million. Note that this owner has purchased more than $16 million worth of the stock since the beginning of July and has a stake of over 3.37 million shares.

Fast Acquisition intends to merge with the casino and restaurant holdings of Tilman Fertitta, which includes Golden Nugget, Bubba Gump Shrimp, Joe's Crab Shack and many other brands. The stock closed Friday's trading at $11.61, within that insider's purchase price range. It has traded between $9.59 and $14.10 a share thus far.

Blackstone

Alternative investment management company Blackstone Group Inc (NYSE: BX) had a beneficial owner add to its stake by buying 150,000 shares in the past week. The purchase price was $16.00 a share, and that added up to $2.40 million. Including preferred shares converted to common shares, that stake was reported as over 3.75 million shares.