Quantum Stocks Are Up 30%. How Much Should You Actually Own?

The quantum computing rally on Thursday was dramatic. D-Wave up 33%, Rigetti up 30%, IBM up 12%. A USD 2 billion government grant package triggered one of the sharpest single-day moves in the sector's history.

If you have zero exposure, you're probably asking whether you missed it. If you have some exposure, you're probably asking whether to add more. Both questions are worth thinking through carefully, because the "right" answer depends almost entirely on how you think about speculative positions in a portfolio.

The core tension

Quantum computing is a real technology with genuine long-term potential. The government backing announced Thursday meaningfully de-risks the sector's survival timeline. These are facts.

At the same time, QBTS and RGTI are pre-profit companies with uncertain commercialisation schedules, now trading at prices that have already absorbed a significant catalyst. You are not buying the same bet that existed 48 hours ago. The risk/reward has shifted.

A framework for sizing

For speculative technology themes where the technology is real but the timing is uncertain, I think about position sizing in three tiers:

Tier 1 (0-2% of portfolio): You believe in the theme but are honest that the timing is unpredictable. This size lets you participate without the position size forcing emotional decisions if it drops 50%.

Tier 2 (2-5% of portfolio): You have a reasoned view on which companies are best positioned and are willing to hold through multi-year volatility. This requires genuine conviction, not just FOMO.

Tier 3 (5%+): You have done deep technical and commercial analysis and are treating this as a core holding. Very few retail investors are actually in this category for quantum specifically.

The mistake to avoid

The most common error after a 30% single-day move is buying at Tier 2 or Tier 3 sizing because of FOMO, when your actual conviction level only justifies Tier 1. The gap between what you feel like doing and what the analysis supports is where losses happen.

Quantum computing will likely be a significant industry over the next decade. Whether QBTS at today's price and RGTI at today's price are the right vehicles to capture that upside is a separate question — and one that deserves more than a day's worth of consideration after a 30% gap up.