How to Short a Bubble

Alexander Campbell · Campbell Ramble · May 12, 2026 at 16:56 · ⏱ 15 min read  | Read on Substack ↗
Summary
Alexander Campbell argues that while it's unknowable whether we are in a bubble, the best ways to position are to find a 'wedge' (e.g., rising rates), short a 'victim' with convex downside, or wait for trend confirmation. He personally hedged by shorting SPX and HYG ahead of a CPI print and sold some Canadian bank exposure, but cautions against shorting the bubble directly.
  • The author shorted 5% more of SPX and 10% of HYG as a hedge before the CPI print confirmed rising inflation.
  • He identifies three ways to short a bubble: find the wedge (rates), short the victim (non-convex correlated asset), or wait for trendline confirmation.
  • Canadian banks trading at 3x book with negative amortizing mortgages are on his watchlist as a potential wedge, though he could not get desired options.
  • He believes the AI revolution is real but cannot tell if current price action is a bubble; he feels underinvested long yet hedges due to drawdown risk.
  • Shorting a bubble directly is difficult because exposure grows exponentially and options become expensive (160 vol).
  • Evergrande is cited as a past example of shorting the victim rather than the bubble itself.
  • The author did not short semiconductors because core demand remains intact.
  • He sold 5% of his Canadian bank positions as part of his risk reduction.
Read time 15 min
Length 15,346 chars
Category finance
Trade Ideas
Alexander Campbell Founder & CEO, Rose AI; ex-macro investor, Bridgewater
Hedging against bubble risk via the wedge of rising rates; SPX short as a macro hedge.
Alexander Campbell Founder & CEO, Rose AI; ex-macro investor, Bridgewater
Shorting high-yield bonds as a wedge play; credit markets vulnerable if bubble pauses.
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This newsletter, published May 12, 2026, features Alexander Campbell discussing SPY, HYG. 2 trade ideas extracted by AI with direction and confidence scoring.

Speakers: Alexander Campbell  · Tickers: SPY, HYG