Updated 3/8, 12:05 PM.

After the market opened Tuesday, Chesapeake’s shares shed about 17% as oil prices pulled back, reversing a recent rally in the crude market. The stock moved in tandem with several of its energy producing peers, including Southwestern Energy swn and SeaDrill sdrl , which dropped about 14% and 17% respectively. Chesapeake shares are still up 57% in the last week.

After the deaths of high-profile singers like David Bowie and Amy Winehouse, sales of their music often suddenly soars, as mourning fans remember the late celebrities. A similar phenomenon appears to be happening to Chesapeake Energy.

Aubrey McClendon, the founder and former CEO of Chesapeake chk and one of the fracking industry’s best known executives, died in a fiery car crash last week. Since then, Chesapeake’s shares have nearly doubled over the past week, rising 94% since last Tuesday’s close. Indeed, Chesapeake’s shares had their largest percentage weekly gain ever last week, even as the company was in the news for unfortunate reasons, with McClendon indicted on federal antitrust conspiracy charges on Tuesday, and then dying in the car crash on the following day. While other energy stocks rose as well last week as oil prices rebound, the sector couldn’t touch Chesapeake’s performance. Chesapeake’s shares were up another 3% on Monday to just over $5.20.

Part of the Oklahoma-based company’s surge can be attributed to its announcement following McClendon’s indictment that it received immunity from criminal prosecution for its cooperation with the investigation. That was a relief to investors, who pushed the price of Chesapeake’s shares higher when the market opened on Wednesday. The stock may have also bounced higher because it was coming off an all-time low price of $1.59 in February.

But none of those factors entirely explain why Chesapeake’s shares rose so much last week, an exceptional rise that at least in part does seems to be tied to McClendon’s death, stock trading patterns reveal.

Trading volume in Chesapeake shares was more than triple its normal levels last Wednesday—but not until the news broke of McClendon’s fatal crash. As shown in the chart below (bottom level, above the third cluster of blue news flags), volume suddenly spiked shortly before 3 p.m., almost exactly as TV outlets aired photos of McClendon’s mangled vehicle.

Trading volume in Chesapeake shares suddenly spiked on March 2, shortly before 3 p.m., as news broke of former CEO McClendon's death.
Trading volume in Chesapeake shares suddenly spiked on March 2, shortly before 3 p.m., as news broke of former CEO McClendon’s death.Data from Bloomberg

The surge in volume also coincided with a similar spike in tweets and social media mentions of Chesapeake, most of which referenced McClendon’s death, triggering a “social velocity” alert on the company for investors using Bloomberg’s data terminal.

A Bloomberg terminal shows a "social velocity" spike on Chesapeake Energy on March 2 as tweets about the company mentioning Aubrey McClendon's death (see examples below chart) surged.
A Bloomberg terminal shows a “social velocity” spike on Chesapeake Energy on March 2 as tweets about the company mentioning Aubrey McClendon’s death (see examples below chart) surged.

Just the social media surge may have been enough to juice Chesapeake’s stock, as hedge funds and algorithmic traders in particular are increasingly using Twitter and social media sentiment signals to decide, or rather have their lightning quick computers decide, which stocks to buy and sell. They can’t, however, always interpret whether a spike in tweets about a subject is bullish or bearish. (In at least one infamous trade, sarcastic tweets about Lululemon lulu see-through pants triggered hedge funds to buy the retailer’s stock, when they would have been better off shorting it.)

You wouldn’t think the same impulse that makes fans buy their deceased idols’ albums would apply to investors buying shares in a company when its leader (or founder) dies. After all, stock isn’t exactly a collector’s item, as musical records may be. If anything, a CEO’s death typically has the opposite effect on a company’s stock price, as witnessed with the 2014 passing of the CEO of French oil giant Total tot and Steve Jobs of Apple aapl in 2011.

But in the case of McClendon, whose alleged sweetheart deals had continued to ensnare Chesapeake in legal issues for years, even after he resigned as CEO in 2013, the knowledge that the executive would no longer be able to exercise his influence on the company may very well have been a weight off investors’ minds.