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Otis Chodosh
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One striking example of the failure of Hamilton-Ivey pinching can be seen here in which it is shown that the FIK shrinkers (which do not have non-negative Ricci curvature, much less non-negative sectional curvature), can arise as blowup limits to the Ricci flow.

As far as I know, basically all that is known is that ancient solutions to the Ricci flow (e.g. blowup limits) have non-negative scalar curvature, by Corollary 2.5 here

Otis Chodosh
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