There is also the small matter of the US presidential election to take on board. You get some idea of how institutional sentiment is playing out through a recent client poll conducted by Nomura (TYO: 8604), which suggested that the worst-case scenario for the S&P 500 would be if there was to be no clear winner on election night, whereas the most favourable index reaction would occur if Donald Trump was re-elected and the US Senate remained in Republican hands. You would imagine, however, that indices could also come under pressure if a newly mandated Trump administration took aim at the heavily weighted tech companies over their immunity from civil liabilities under section 230 of the Communications Decency Act, in addition to the antitrust measures already in train. Any such move could conceivably attract a degree of bipartisan support in the US Congress.
The plain fact that the S&P 500 is still bubbling around all-time highs provides a clear incentive to file for an IPO, while market valuations in the US regularly exceed pre-listing estimates. It seems that investors have become more willing to bid-up the value of newly listed companies in expectation of future growth, particularly where market-disrupting tech stocks are concerned. But there is a chance that some big-name listing prospects could find themselves left in the blocks when the market runs out of steam.