Nordsight — learn to invest, properly

You've picked a theme for your satellite. Now comes the part where most people quietly wreck it: they buy fifteen things that all sound on-theme, end up holding the same companies three times over, and pay a fee drag they never look at again. This lesson is about doing the opposite — expressing a theme cleanly with three to five instruments, chosen by a checklist you run yourself.

This is education, not a recommendation

Everything below is about how to choose — the method, the filter, the trade-offs. We deliberately name zero instruments to buy. Any example is only an illustration of how a theme is commonly expressed, never a pick to act on. What goes in your satellite is your decision, made against your own situation.

Two ways to express a theme

Say your satellite theme is "European defense." You don't buy "the theme" — you buy instruments that track it. Broadly, you have two routes, and most good satellites are a blend.

Route one

One ETF = the theme in a ticker

A thematic ETF holds dozens of companies in the space, weighted by a rule. You get the theme in a single line, instantly diversified across the names, and the fund handles rebalancing. The cost is a yearly fee (the TER) and the fact that you own the index's definition of the theme — including names you might not have chosen.

Route two

A few single names = your own cut

You pick a handful of individual companies you believe best express the theme. More control, potentially more upside if you're right — and a lot more idiosyncratic risk: one company's accounting scandal, lawsuit, or bad quarter hits your whole position. A single name can go to zero. A broad ETF essentially cannot.

The honest trade-off

The ETF buys you breadth and removes single-company risk, at the price of a fee and someone else's definition of the theme. Single names buy you conviction and precision, at the price of concentration risk you carry alone. A common, sane satellite is one broad ETF as the spine, plus one or two single names you actually have a view on — illustration of a structure, not a recommendation.

The filter checklist — run this on every candidate

Before any instrument earns a slot, put it through these five questions. If it fails one badly, it's out — there's almost always another way to express the same theme that passes. This is the work that separates a deliberate satellite from a pile of things you bought because they were trending.

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1 · Cost — what's the TER, and is it justified?
For an ETF, the Total Expense Ratiois the yearly fee, quoted as a percentage. A broad index fund might charge a small fraction of a percent; a niche thematic one charges several times more. Higher isn't automatically wrong — but a fee is a guaranteed cost, every year, win or lose. Ask whether the theme genuinely needs that wrapper, or whether a cheaper one gets you the same exposure. For single stocks the cost is the spread and any commission — check both.
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2 · Liquidity — can you get in and out without bleeding?
Look at average daily volume and the bid-ask spread. A thin, rarely-traded instrument means you pay a hidden tax every time you transact, and in a panic you may not be able to exit at a fair price. Prefer instruments that trade actively. Wide spreads on a small ETF are a red flag.
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3 · Tracking — does it actually express your theme?
Read the holdings. A fund with "clean energy" in its name might be 30% utilities you'd never call clean-energy plays. A "defense" ETF might be dominated by diversified conglomerates where defense is a small slice of revenue. Open the top-ten holdings and the sector breakdown and confirm the thing does what the label promises. Label ≠ contents.
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4 · Overlap — does it duplicate your core?
Your core (the boring, diversified base from earlier modules) probably already holds the mega-caps. If your "AI" satellite ETF is 25% the same three giant tech names you already own in your core, you're not adding a satellite — you're just over-weighting your core and calling it a theme. Check the overlap and discount it.
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5 · Domicile — is it UCITS / EU-appropriate?
As an EU retail investor, you generally can only buy ETFs that are UCITS-compliant (a European regulatory standard) — many US-domiciled funds simply aren't available to you, and buying around that creates tax and paperwork headaches. Check the domicile (often visible in the name — e.g. an Irish-domiciled UCITS fund) and that it's actually purchasable in your account before you fall in love with it.

A candidate has to pass the whole list

One green flag doesn't save a candidate. A perfectly on-theme ETF that's illiquid and not UCITS-available is useless to you. A cheap, liquid, EU-available fund that doesn't actually track your theme is just a random holding. The point of the checklist is to make you say no on purpose.

Why 3-5 and not 15

There's a strong pull toward holding more — it feelssafer, more thorough. For a small satellite it's the opposite of useful. Past a handful of well-chosen instruments, each new one barely changes your exposure but adds something to track, more fees, more overlap, and more chances to fool yourself into thinking you've diversified when you've really just diluted into mush.

One broad ETF already is diversification.It can hold fifty companies. Adding fourteen more tickers on top doesn't meaningfully reduce risk — it just clutters.
You can't actually follow fifteen theses.A satellite is a view you hold on purpose. If you can't state in a sentence why each instrument is there, it shouldn't be there.
More lines, more fees and more overlap. Each holding is another TER or spread, and niche funds tend to own the same handful of leaders — so you pay more to own the same thing.

Concentration inside a satellite is fine — because the satellite is small

Here's the part that confuses people. We spent earlier modules preaching diversification — now we're saying it's okay for a satellite to be concentrated in three to five instruments, maybe even tilted toward one. Both are true, and the reconciling fact is position size.

A satellite is a small, deliberate slice of the whole portfolio — the kind of single-digit-percent allocation you set in the previous lesson. Concentration is dangerous when it's the bulk of your money. When the satellite is small by design, a concentrated bet inside it can fail completely and still only dent the total. That's the whole point of the core-and-satellite shape: the core stays diversified and boring so the satellite is allowed to have a sharp, concentrated opinion.

Try first

Your defense satellite is two instruments and it just dropped 30% on bad news. You feel sick and want to add five more defense ETFs "to spread the risk." Is that the right move?

What's next

You now have a theme, a sizing rule, and a filtered set of three to five instruments. The next lesson is about writing the satellite's thesis and exit conditions down before you act — so that future-you, mid-drawdown, has a sober note from past-you to read instead of a panic to obey.