Bought more Coinbase in the Trading 212 SIPP today. I opened this position only recently — coffee, consoles and crypto, as the post title went — and here I am topping it up already. Why not, eh?
The thesis hasn't changed in the short time since I opened it. Coinbase is the largest regulated crypto exchange in the United States, and it's evolving beyond pure exchange into custody, staking, and infrastructure (the Base layer-2 blockchain built on Ethereum). It survived multiple crypto winters and came out stronger — gaining market share while competitors collapsed or fled. The regulatory environment is gradually clarifying, and Coinbase is well-positioned to benefit if (and it's still an if) crypto matures as an asset class.
The risks haven't changed either. Crypto trading volumes are cyclical and can stay depressed for years. The SEC and other regulators could restrict Coinbase's business model — particularly around staking services. Competition from decentralised exchanges, Binance, and traditional finance giants like BlackRock and Fidelity is real and intensifying. And COIN the stock is wildly volatile — it can move 20% in a week on nothing more than a change in crypto sentiment. This remains a speculative position, sized accordingly.
── Why Top It Up? ──
Sometimes the honest answer to 'why did you buy more?' is simpler than a 2,000-word thesis. I had a bit of spare capital in the SIPP after setting up the Pie. I looked at my positions. COIN is still small — the smallest satellite in the portfolio alongside Amesite. The conviction hasn't wavered. And the price was roughly where it was when I opened the position, so I wasn't chasing it up. Same thesis, same price ballpark, same small position size — adding a little more felt consistent rather than impulsive.
There's a difference between sizing up a position because you're chasing performance (bad) and sizing up because the position was deliberately small to begin with and you're comfortable letting it grow gradually (fine). The first time I bought COIN, I described it as a conviction satellite — small enough that a significant drawdown wouldn't materially impact the overall SIPP, but large enough that the compounding matters if the thesis plays out. Today's top-up keeps it in that zone. Still a satellite. Still speculative. Still not betting the farm.
── The 'Why Not?' Test ──
There's a little mental framework I use when I'm considering topping up a small position, and it goes like this. Ask yourself three questions. One: has anything materially changed about the business since you last bought it? Two: would you be comfortable owning more at this price if the stock dropped 30% tomorrow? Three: is the position still sized so that being completely wrong doesn't change your financial life?
For COIN, the answers were: no (nothing material has changed), yes (volatility is priced into the thesis), and yes (it's still tiny relative to the core VUAG and VWRP holdings). When all three answers are yes, the 'why not?' is genuinely just 'why not.' Not every buy needs a dramatic catalyst or a multi-page thesis. Sometimes you just have conviction, the position is small, and adding a bit more is consistent with the plan.
So I added a bit more. It's still a speculative punt on crypto infrastructure. It's still going to be a volatile ride. I'm still prepared for it to go nowhere — or to zero, if crypto winter returns with a vengeance. But the thesis is intact, the sizing is sensible, and the upside, if crypto does mature over the next decade or two, is material. Why not, eh?
As always: this is what I did with my own money. Not a recommendation. All investing carries risk — you can lose money, and past performance doesn't predict future returns. Coinbase (COIN) is a speculative position carrying specific and significant risks including crypto market volatility, regulatory uncertainty, business model risk, competitive pressure, and the possibility of total capital loss. US-listed shares carry currency risk for UK investors. Do your own research.