Bitcoin is gyrating amid rallying global stock markets while ether options traders ramp up open interest as the Ethereum network heads for an ambitious upgrade.

After bitcoin rallied over $200 on news that Pfizer’s vaccine trial showed it was 90% effective in preventing coronavirus infections, the price suffered a drop of almost $1,000 within hours Monday. The sell-off went from $15,842 shortly after Pfizer’s announcement early in the morning to as low as $14,845 around 16:30 UTC (8:30 a.m. ET). It has since recovered, changing hands at $15,389 as of press time, according to CoinDesk 20 data. 

“Bitcoin’s retracement through the $15,000 level is a continuation of the gradual move downward during the past few days,” said Guy Hirsch, managing director for U.S. at multi-asset brokerage eToro. “Though today, it feels different than the likely profit-taking that occurred over the weekend.”

Cindy Leow, portfolio manager for multi-strategy crypto trading firm 256 Capital Partners, has been tracking bitcoin’s volume-weighted average price, or VWAP, as a indicator as prices take a break from a rally that took the world’s oldest cryptocurrency to record 2020 highs the past week. VWAP gives an average price at which an asset has traded throughout the day based on both volume and price.

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“In the short term, we're entering into whipsaw markets that typically follow huge gains,” Leow noted. “We see immediate support at BTC's monthly VWAP of $14,700, from which BTC has steadily bounced off of, indicating that buyers still maintain control.” 

A change in market dynamics is also playing a role in staving off possible price downside. That’s due in large measure to the waning influence of leveraged derivatives venue BitMEX, which is facing lawsuits and the ire of U.S. regulators. 

“It's fascinating that this whole move up last week from $13,900 to $15,900 happened with so few long liquidations and barely any corrections so far,” Leow said. “We suspect this is largely an effect of trading volumes going from BTC-margined futures to USDT-margined futures, as USDT-margined traders are by default technically in a short BTC position.” 

Liquidations on BitMEX, as tracked by data aggregator Skew, are on the decline.

Meanwhile, traditional markets are seeing major action Monday, the first trading day since a clear winner in the U.S. presidential election was decided. Former Vice President Joe Biden is set to take office in early 2021.

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Stocks are up across major global indices.

In addition, big moves are occuring in major commodities, with oil way up and gold way down.

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“With the S&P 500 touching a new all-time high today alongside news of a Pfizer COVID vaccine showing strong promise, it will be interesting to see how BTC behaves in the weeks ahead,” said Daniel Kohler, liquidity manager at San Francisco-based cryptocurrency exchange OKCoin. “For the past few weeks we were seeing a rise in BTC and S&P 500 correlations — with BTC trading at levels not seen since 2017, it will be interesting to see if that trend reverts or we continue to see outperformance.”

In fact, the trend does already seem to be reverting, with correlation dropping this past week through Friday’s close.

“Surprisingly, given the recent correlation with equities, bitcoin’s immediate price action has been much more choppy,” added Denis Vinokourov, head of research at crypto brokerage Bequant.

The second-largest cryptocurrency by market capitalization, ether (ETH), was down Monday trading around $447 and slipping 1% in 24 hours as of 21:00 UTC (4:00 p.m. ET).

Open interest in ether options hit a record high Sunday, at over $570 million. The last time open interest approached that level was Sept. 1, when it was at $544 million.

Greg Magadini, chief executive officer of data aggregator Genesis Volatility, says the progress of the Ethereum’s network’s move to upgrade to “2.0” has options traders increasingly placing their bets on the outcome. 

“On the night of the U.S. elections, we saw the quiet release of the ETH 2.0 deposit contract,” Magadini told CoinDesk “As we inched closer to the launch of Phase 0 the excitement triggered an increase in ETH option volume traded last week.”

Digital assets on the CoinDesk 20 are all red Monday. Notable losers as of 21:00 UTC (4:00 p.m. ET):

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Treasurys: