With U.S Federal Reserve policy easing drawing to a close, Societe Generale's uber-bearish strategist Albert Edwards predicts that a bubble in stock markets is on the verge of bursting.
"Is that a hissing I can hear?" Edwards quipped in his latest research note, published on Thursday.
Edwards claimed the "share buyback party"—which some analysts see as the key driver for recent record Wall Street highs—was now over.
"Companies themselves have been the only substantive buyers of equity, but the most recent data suggests that this party is over and as profits also stall out, the equity market is now running on fumes," Edwards said.
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Buybacks occur when firms purchase their own shares, reducing the proportion in the hands of investors. Like dividend payments, buybacks offer a way to return cash to shareholders, and usually see a company's stock push higher as shares get scarcer.
According to Societe Generale's research, share buybacks fell by over 20 percent the second quarter versus the first quarter. However, TrimTabs Chief Executive David Santschi said in a research note on Sunday that buyback announcements were "solid" as earnings season wrapped up.
Some firms borrow cash to buy back their shares, taking advantage of ultra-low interest rates in the U.S. and other developed nations. Edwards warned that as companies had issued cheap debt to buy expensive equity, a "gargantuan" funding gap could yet emerge.
"The equity bubble has disguised the mountain of net debt piling up on U.S. corporate balance sheets. This is hitting home now QE has ended. The end of the buyback bonanza may well prove to be decisive for this bubble," Edwards wrote.
Edwards is known for his markedly pessimistic predictions, and regularly touts the idea of an economic "Ice Age" in which equities will collapse because of global deflationary pressures.
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Some analysts remain unconvinced. MacNeil Curry, head of global technical strategy at Bank of America Merrill Lynch, sees no imminent hit to equities. He predicts further upside for the —currently near all-time highs—over the next few weeks, and sees the benchmark index reaching 2,050-to-2,060 points by late September.