• Insider buying can be an encouraging signal for potential investors, especially when markets face uncertainty.
• Some insiders have taken advantage of recent biotech initial public offerings.
• Some chief executives also stepped up to the buy window this past week.

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 at near all-time highs.

Here are some of the most noteworthy insider purchases that were reported in the past week.

Vor Biopharma Inc VOR saw two 10% owners acquire almost 3.5 million shares in its IPO. At an offering price of $18.00, the total for those purchases came to more than $63.63 million. Shares ended this past week trading at $48.78, after going as high as $63.62 after the IP

Lucira Health Inc LHDX had a 10% owner buy shares of in the initial public offering. The more than 3.46 million shares acquired, at $17.00 apiece, totaled nearly $58.85 million. The stock has traded as high as $35.72 so far and closed most recently at $33.49 per share.

CEO William Quinn acquired 1,200 Bolt Biotherapeutics Inc BOLT shares in the IPO, while other insiders bought up over 1.85 million shares. At $20.00 per share, those transactions totaled more than $37.12 million altogether. The stock closed most recently at $33.31 a share.

Three 10% owners picked up more than 1.61 million shares altogether of Terns Pharmaceuticals Inc TERN. That cost them more than $27.45 million, at the IPO price of $17.00 per share. Shares went as high as $23.68, before ending the week at $18.09 apiece.

In the wake of the Landos Biopharma Inc LABP IPO, a beneficial owner added to its stake. Almost 3.66 million shares were acquired at prices ranging from $10.96 to $16.00. That totaled over $22.90 million. The IPO price was $16.00, but the stock was last seen trading at $13.00.

CEO William Furman bought 50,000 Greenbrier Companies Inc GBX shares last week for $42.91 to $44.00 apiece. The total for that came to more than $1.31 million. Note that other insiders sold over 27,800 shares last week. The stock ended last week trading at $45.98 per share.

Dun & Bradstreet Holdings Inc DNB CEO Anthony Jabbour and another officer scooped up a combined 47,900 shares last week. At prices between $23.10 and $23.42 per share, that cost them more than $1.11 million. Jabbour's stake was last up to about 415,800 shares.

At Curiositystream Inc CURI, a director added 74,000 shares to his stake early last week. Those shares cost $13.50 apiece, and the purchase totaled $999,000. This lifted his stake to more than 896,100 shares. The stock ended last week's trading at $18.69 per share, or up about 34% year to date.

Affiliated Managers Group, Inc. AMG had CEO Jay Horgen and another director step up to the buy window after earnings. The 6,500 shares they acquired, at prices of between $136.00 and $145.53, added up to more than $908,700. The stock closed most recently at $147.90.

And Calix Inc CALX had a director indirectly acquire 20,000 of its shares. At an average share price of about $35.75, that added up to more than $714,900. This software company's stock ended Friday trading at $36.80 per share, after a pop of more than 12% in the past week.

Note that some smaller amount of insider buying at Anthem Inc ANTM, Arch Resources Inc ARCH, Biogen Inc BIIB 0.28%, Crown Castle International Corp CCI, Molson Coors Beverage Co TAP, Norfolk Southern Corp. NSC and Sally Beauty Holdings, Inc. SBH was reported in the past week as well.