Insider buying can be an encouraging signal for potential investors.

Two energy companies saw insiders return to add to their stakes last week.

Executives at a biotech company took advantage of a pullback to buy shares.

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. So insider buying can be an encouraging signal for potential investors, particularly with markets near all-time highs.

PBF Energy

A 10% owner of PBF Energy Inc. (NYSE:PBF) scooped up more than 293,400 shares of this New Jersey-based refiner last week.

At prices ranging from $29.72 to $29.94, that totaled less than $8.75 million, and it followed the purchase of more than 1.11 million shares in the previous week.

PBF posted better-than-expected third-quarter results. The stock was last seen trading at $29.86 per share — still within the above purchase price range — after retreating more than 12% since the earnings report.

The 52-week trading range is $21.10 to $37.03, and the consensus analyst recommendation is to buy the shares.

Enterprise Products Partners

An Enterprise Products Partners L.P. (NYSE:EPD) director stepped up to the buy window again this past week. That director picked up an additional 201,000 shares via trust of this midstream energy services provider at $26.11 to $26.73 each. That totaled about $5.31 million. The same director bought more than 1.16 million shares in the prior week.

Sage Therapeutics

SAGE Therapeutics Inc (NASDAQ:SAGE) saw its CEO Jeffrey Jonas purchase 7,500 shares and its chief scientific officer buy 25,000 shares. At prices ranging from $63.77 to $64.49 per share, that cost them more than $2.08 million altogether. Jonas' purchase lifted his stake to over 54,500 shares.

The release of disappointing trial results took a big bite out of the stock last week. Its shares were trading at $72.87 each on last look, so the purchases appear to be well-timed. The stock has traded as high as $193.56 in the past year, and the consensus analyst price target is $109.11.

See also: Restoration Hardware CEO, 6 Other Execs Sell Shares

Note that there also was some insider buying at the former BB&T, now known as Truist Financial Corp (NYSE:TFC), and at Dow Inc (NYSE:DOW) in the past week.

At the time of this writing, the author had no position in the mentioned equities.

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