This contrarian indicator says the oil rally is over

Energy stocks have slid in the past three sessions, after a big bounce since mid-March, and the options market could be throwing off signs that the comeback is over for good.

In a recent note to clients, Goldman Sachs' options research team wrote: "We recently changed our view from bullish to bearish on energy as option markets show extreme complacency following the sharp rally in the energy complex over the past six weeks."

Specifically, Goldman found that the prices of bearish put options have fallen considerably, indicating that investors see diminished risk of downside as traders have become far more optimistic. But for Goldman, that's a clear sign that the energy rally has run out of steam.

"We find options have been a powerful contrarian indicator over the past year," and once again, it will pay to look the direction that the market isn't looking, the analysts concluded.

Yet Susquehanna head of derivative strategy Stacey Gilbert says it's only logical that options prices have fallen.

"There is a sense of complacency, but let's put the complacency into context," Gilbert said Thursday on CNBC's "Trading Nation." "The volatility was substantially higher if you go back over the past six months compared to where it's pricing everything now … [but] the question becomes, are we having the same type of movement that we've had over the past six weeks?"

"If you're not expecting that type of movement, volatility should be lower," she added.

Gilbert says the options market is predicting that crude oil will remain range-bound at $50-$70 a barrel, rather than continuing to make massive moves, although implied volatility is still elevated versus recent historical averages.

But to Gilbert, just because the options market is pricing in smaller swings over the next few months than the gargantuan ones the energy market has experienced over the last few months, that doesn't mean energy stocks are set to sink.

Disclosure: Gilbert holds a bullish options position on the Market Vectors Oil Services ETF (OIH).

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