A bear flattener is a yield curve regime where bond prices fall (yields rise) and the curve flattens (the spread between long and short rates narrows). This is the signature pattern of a Federal Reserve tightening cycle.
The mechanics:
Short-term yields rise sharply as the Fed raises the funds rate and the market prices in further hikes
Long-term yields also rise, but by less, because the market anticipates that tightening will eventually slow the economy and limit how far long rates need to go
The net effect is a flatter curve, and if sustained, inversion
Bear flatteners dominated the 2022-2023 period as the Fed raised rates from near-zero to above 5%. The 2-year yield surged, while the 10-year yield rose more moderately, producing the deepest curve inversion in decades.
For portfolio positioning, bear flatteners are punishing for:
Long duration positions (rising rates reduce bond prices)
Steepener trades (the curve moves against them)
Defensive strategies include shortening duration, moving into floating-rate instruments, or positioning for the eventual transition to a different regime when the tightening cycle ends.