24/7 Wall St.

One thing we have watched when looking for a sign of an oil turnaround was substantial insider buying of shares. While the action had been consistent, nothing huge hit the tape. That all changed this week, and energy investors may be very excited to see this kind of purchase. It is the kind that makes a pretty clear statement to the markets that the long-term outlook for the energy sector still remains bright.

We cover insider buying each week here at 24/7 Wall St., and the number of high level executives and 10% institutional owners adding to positions is much higher than in recent weeks. With buying windows opening up wide now after first-quarter reports, we could see a continued increase in some sectors like we did energy.

The following companies reported notable insider buying this week.

Chevron Corp. (NYSE: CVX) had a director step up to the plate in a big way this week. That director bought a gigantic 180,000 share block of the stock at $108.10 apiece. The total ticket for this monster insider purchase was $19.5 million. Shares of the company were trading at $108.03 on Friday’s close.

zulily Inc. (NASDAQ: ZU) had a well-known 10% owner buy a huge block of stock. Chinese Internet giant Alibaba scooped up 4.81 million shares at prices ranging from $10.82 to $12.12 per share. The total came to a whopping $56.15 million. zulily operates as an online retailer in the United States, Canada, Australia, the United Kingdom and elsewhere. The stock ended trading Friday at $13.51.

ALSO READ: 5 Big Oil Stocks to Buy for the Rest of 2015

Republic Services Inc. (NYSE: RSG) was a frequent visitor to our insider buying screens last year and returns in a big way. Cascade Investments, the private investment arm of Microsoft founder Bill Gates, has again added to its position in the waste management company. Cascade bought a whopping 1.35 million shares at prices that ranged from $39.65 to $40.25. The total came to a massive $54.1 million. Shares closed trading Friday at $40.74.

Cumulus Media Inc. (NASDAQ: CMLS) also had a 10% owner adding shares to its book this past week. Crestview Radio Investors bought 807,173 shares. At prices that ranged from $2.11 to $2.34, the total for the purchase came to $1.9 million. Cumulus Media owns and operates radio stations in the United States. It sells commercial advertising time to local, national and network clients on its radio stations. The company owns and operates approximately 460 stations in 90 United States media markets, and approximately 8,500 broadcast radio affiliates and various digital channels. Shares ended the week at $2.38.

Qualys Inc. (NASDAQ: QLYS) got blasted when earnings and guidance disappointed recently. Shareholders will be glad to know that a director at the company is still positive. That director bought a block of 50,000 shares this past week at $37.51 apiece. The total for the buy came to $1.9 million. The company provides cloud security and compliance solutions in the United States and internationally. Shares closed trading on Friday at $38.61, so a well-timed buy indeed.

ALSO READ: Very High-Profile Insider Selling Marks Roller-Coaster Market Week

These other companies also reported insider buying this week: Annaly Capital Management Inc. (NYSE: NLY), Covanta Holding Corp. (NYSE: CVA), Keurig Green Mountain Inc. (NASDAQ: GMCR), Sears Holdings Corp. (NASDAQ: SHLD) and Wynn Resorts Inc. (NASDAQ: WYNN).

In a very bullish note for the markets, insider buying volume was significantly higher than insider selling this past week. This is very good and bodes well for the rest of the summer and 2015.